MikaStars39/nano-eval huggingface dataset:
The following liquid-phase reactions are carried out in a batch reactor:
$$
\mathrm{A + B} \rightleftharpoons \mathrm{R}, \\\mathrm{A + R} \rightleftharpoons \mathrm{S}.
$$
The initial concentrations of the reactant mixture are:
$$
c_{\mathrm{A 0}} = 2 \, \mathrm{mol/L},
$$
$$
c_{\mathrm{B 0}} = 4 \, \mathrm{mol/L},
$$
$$
c_{\mathrm{R 0}} = c_{\mathrm{S 0}} = 0.
$$
After the reaction time $t$, the concentrations are measured as $c_{\mathrm{A}} = 0.3 \, \mathrm{mol/L}$ and $c_{\mathrm{R}} = 1.5 \, \mathrm{mol/L}$. What are the concentrations of components B and S?

Options:
A. $$
\begin{array} {c} {{{c_{B}=2. 4 ~ \mathrm{m o l / L}}}} \\ {{{c_{S}=0. 1 ~ \mathrm{m o l / L}}}} \\ \end{array}
$$
B. $$
\begin{array} {c} {{{c_{B}=2. 6 ~ \mathrm{m o l / L}}}} \\ {{{c_{S}=0. 0 ~ \mathrm{m o l / L}}}} \\ \end{array}
$$
C. $$
\begin{array} {c} {{{c_{B}=1. 9 ~ \mathrm{m o l / L}}}} \\ {{{c_{S}=0. 6 ~ \mathrm{m o l / L}}}} \\ \end{array}
$$
D. $$
\begin{array} {c} {{{c_{B}=1. 7 ~ \mathrm{m o l / L}}}} \\ {{{c_{S}=0. 8 ~ \mathrm{m o l / L}}}} \\ \end{array}
$$
E. $$
\begin{array} {c} {{{c_{B}=2. 1 ~ \mathrm{m o l / L}}}} \\ {{{c_{S}=0. 4 ~ \mathrm{m o l / L}}}} \\ \end{array}
$$
F. $$
\begin{array} {c} {{{c_{B}=2. 5 ~ \mathrm{m o l / L}}}} \\ {{{c_{S}=0. 2 ~ \mathrm{m o l / L}}}} \\ \end{array}
$$
G. $$
\begin{array} {c} {{{c_{B}=1. 8 ~ \mathrm{m o l / L}}}} \\ {{{c_{S}=0. 5 ~ \mathrm{m o l / L}}}} \\ \end{array}
$$
H. $$
\begin{array} {c} {{{c_{B}=3. 0 ~ \mathrm{m o l / L}}}} \\ {{{c_{S}=0. 3 ~ \mathrm{m o l / L}}}} \\ \end{array}
$$
I. $$
\begin{array} {c} {{{c_{B}=3. 2 ~ \mathrm{m o l / L}}}} \\ {{{c_{S}=0. 7 ~ \mathrm{m o l / L}}}} \\ \end{array}
$$
J. $$
\begin{array} {c} {{{c_{B}=2. 3 ~ \mathrm{m o l / L}}}} \\ {{{c_{S}=0. 2 ~ \mathrm{m o l / L}}}} \\ \end{array}
$$
Answer: A
The decomposition reaction of nitrous oxide follows a second-order rate equation:
$$
2 \mathrm{N}_{2} \mathrm{O} \longrightarrow 2 \mathrm{N}_{2} + \mathrm{O}_{2}
$$
At 895°C, the forward reaction rate constant $k$ is 977 $\mathrm{cm}^{3}/(\mathrm{mol} \cdot \mathrm{s})$, and the reverse reaction rate can be neglected. The initial pressure is 0.10133 MPa, and at the start of the reaction, the reactor contains only $\mathrm{N_{2}O}$. What are the decomposition rates at times of 1.0 s, 10 s, and 10 min in a batch reactor?

Options:
A. 0.04 ,0.088, 0.830
B. 0.05,0.070,0.890
C. 0.03,0.089,0.840
D. 0.01,0.095,0.800
E. 0.04,0.080,0.820
F. 0.01, 0.092, 0.860
G. 0.02, 0.085, 0.870
H. 0.03,0.091,0.850
I. 0.02,0.083,0.810
J. 0.01,0.090,0.880
Answer: F
Production of 50 t/d of Ethyl Acetate Using a Batch Reactor
Reaction Equation: $(A)$$\mathrm{C}_{2}\mathrm{H}_{5}OH$+$(B)$ $\mathrm{CH}_3COOH$→ $(P)$ $\mathrm{CH}_3\mathrm{COOC}_2\mathrm{H} _5$+$(S)$ $\mathrm{H} _2O$
The raw material ratio is
$$A:B:S=46:23:31(kg/kg)$$
The reaction is conducted isothermally at 100°C, and the reaction rate is calculated by the following formula:
$$\begin{aligned}&\text{}\\&(-r_{\mathrm{B}})=k(c_{\mathrm{A}}c_{\mathrm{B}}-c_{\mathrm{P}}c_{\mathrm{S}}/K)\\&k=2.85\times10^{-2}\:\mathrm{m}^{3}/(\mathrm{kmol}\cdot\mathrm{h})\\&K=2.93\end{aligned}$$
The density of the reaction mixture is 1,020 kg/m$^{3}$. Assuming the final conversion rate of acetic acid, $x_\mathrm{B}$, is 0.35, and accounting for 1 hour required for each batch of loading, unloading, and cleaning, determine the volume of the reactor is ().

Options:
A. $$
6 0 \ \mathrm{m}^{3}
$$
B. $$
4 8 \ \mathrm{m}^{3}
$$
C. $$
4 6 \ \mathrm{m}^{3}
$$
D. $$
5 5 \ \mathrm{m}^{3}
$$
E. $$
5 4 \ \mathrm{m}^{3}
$$
F. $$
5 3 \ \mathrm{m}^{3}
$$
G. $$
5 2 \ \mathrm{m}^{3}
$$
H. $$
5 8 \ \mathrm{m}^{3}
$$
I. $$
4 9 \ \mathrm{m}^{3}
$$
J. $$
4 7 \ \mathrm{m}^{3}
$$
Answer: G
A certain gas-phase first-order decomposition reaction, $\mathrm{A} \longrightarrow3 \mathrm{P}$, proceeds as a first-order reaction and is carried out in an isothermal tubular experimental reactor. The feed consists of 50% $\mathrm{A}$ and 50% inert material. The residence time is 10 minutes, and the volumetric flow rate at the system outlet becomes 1.5 times the original. What is the conversion rate of $\mathrm{A}$ and the reaction rate constant for this reaction under these experimental conditions?

Options:
A. $$
k=0.088 63 L/min
$$
B. $$
k=0.102 18 L/min
$$
C. $$
k=0.097 84 L/min
$$
D. $$
k=0.125 37 L/min
$$
E. $$
k=0.134 72 L/min
$$
F. $$
k=0.049 87 L/min
$$
G. $$
k=0.076 35 L/min
$$
H. $$
k=0.067 42 L/min
$$
I. $$
k=0.112 49 L/min
$$
J. $$
k=0.055 91 L/min
$$
Answer: A
A certain first-order reaction takes place in a completely mixed tank reactor, $(-r_{\mathrm{A}}) = k c_{\mathrm{A}}$, where $k = 0.38 \, \mathrm{min}^{-1}$. Given that the feed reactant concentration is $c_{\mathrm{A0}} = 0.3 \, \mathrm{kmol/m}^3$, the volumetric flow rate is $\upsilon_0 = 20 \, \mathrm{L/min}$, and the required outlet conversion $x_{\mathrm{A}f}$ is 0.7. If the reaction is conducted in a plug flow reactor, what is the required reactor volume?

Options:
A. $$
63.4L
$$
B. $$
50.8L
$$
C. $$
76.5L
$$
D. $$
59.1L
$$
E. $$
47.5L
$$
F. $$
71.2L
$$
G. $$
54.3L
$$
H. $$
80.3L
$$
I. $$
45.7L
$$
J. $$
68.9L
$$
Answer: A
Using an NaOH solution as the tracer, a pulse injection of volume $V \!=\! 1 \ \mathrm{m}^{3}$ is introduced into a continuously stirred tank reactor (CSTR) with a flow rate of $\upsilon\!=\! 1 \ \mathrm{m}^{3} / \mathrm{min}$. The tracer $C-t$ curve is measured in the outlet stream. It is known that the curve can be expressed as $C = 30 \mathrm{e}^{-t / 40}$. Determine the flow behavior inside the reactor is ().

Options:
A. $$
V_{d}=2\ m^{3}
$$
B. $$
V_{d}=\frac{1}{3} m^{3}
$$
C. $$
V_{d}=\frac{3}{4} m^{3}
$$
D. $$
V_{d}=\frac{1}{6} m^{3}
$$
E. $$
V_{d}=0.5\ m^{3}
$$
F. $$
V_{d}=1\ m^{3}
$$
G. $$
V_{d}=\frac{2}{3} m^{3}
$$
H. $$
V_{d}=\frac{1}{2} m^{3}
$$
I. $$
V_{d}=\frac{1}{4} m^{3}
$$
J. $$
V_{d}=\frac{5}{6} m^{3}
$$
Answer: B
The autocatalytic reaction $\mathrm{A} \to \mathrm{P}$ has a rate equation $(-r_{\mathrm{A}}) = k c_{\mathrm{A}} c_{\mathrm{P}}$. The initial concentration of feed $\mathrm{A}$ is $c_{N} = 1 \, \mathrm{mol/L}$, with a trace amount of $\mathrm{P}$. To achieve a final conversion rate of $x_{\mathrm{A}} = 0.99$ and minimize the required reactor volume, a combination of a continuous stirred-tank reactor (CSTR) and a plug flow reactor (PFR) is proposed. If the feed flow rate \(v = 10 \, \mathrm{m}^3/\mathrm{h}\), the rate constant \(k = 4.2 \times 10^{-4} \, \mathrm{m}^3/(\mathrm{mol} \cdot \mathrm{s})\), what intermediate conversion rate should be controlled?

Options:
A. 0.65
B. 0.7
C. 0.6
D. 0.1
E. 0.4
F. 0.85
G. 0.25
H. 0.75
I. 0.9
J. 0.5
Answer: J
A binary gas mixture flows through a spherical catalyst bed with a diameter of 5 mm at an apparent velocity of $0.1 \ \mathrm{m/s}$. The gas density $\rho$ is $1 \ \mathrm{kg}/\mathrm{m}^3$, viscosity $\mu$ is $3 \times 10^{-5} \ \mathrm{Pa} \cdot \mathrm{s}$, and the diffusion coefficient $D$ is $4 \times 10^{-5} \ \mathrm{m}^2/\mathrm{s}$. What is the $S h$ (Sherwood number) between the gas and the packing material?

Options:
A. 8.12
B. 8.00
C. 7.25
D. 7.06
E. 6.95
F. 6.85
G. 7.80
H. 8.05
I. 7.50
J. 6.50
Answer: D
An irreversible gas-solid catalytic reaction has a reaction rate of
$$
(-r_{\mathrm{A}} ) \!=\! k c_{\mathrm{A}} \!=\! 10^{-6} \, \mathrm{mol} / (\mathrm{s \cdot cm}^{3})
$$
When $c_{\mathrm{A}} \!=\! 10^{-2} \, \mathrm{mol/L}$, the pressure is 0.10133 MPa, and the temperature is 400°C. To ensure that internal diffusion within the catalyst does not significantly affect the overall reaction rate, how should the catalyst particle diameter be adjusted?
It is known that $D_{\mathrm{e}} = 10^{-3} \, \mathrm{cm^{2}/s}$.

Options:
A. $$
R_{\mathrm{P}} \!=\! 0. \ 2 5 \mathrm{c m} \!
$$
B. $$
R_{\mathrm{P}} \!=\! 0. \ 3 \mathrm{c m} \!
$$
C. $$
R_{\mathrm{P}} \!=\! 0. \ 4 \mathrm{c m} \!
$$
D. $$
R_{\mathrm{P}} \!=\! 0. \ 1 \mathrm{c m} \!
$$
E. $$
R_{\mathrm{P}} \!=\! 0. \ 0 5 \mathrm{c m} \!
$$
F. $$
R_{\mathrm{P}} \!=\! 0. \ 0 8 \mathrm{c m} \!
$$
G. $$
R_{\mathrm{P}} \!=\! 0. \ 2 \mathrm{c m} \!
$$
H. $$
R_{\mathrm{P}} \!=\! 0. \ 6 \mathrm{c m} \!
$$
I. $$
R_{\mathrm{P}} \!=\! 0. \ 7 \mathrm{c m} \!
$$
J. $$
R_{\mathrm{P}} \!=\! 0. \ 5 0 \mathrm{c m} \!
$$
Answer: D
What is the time response of the following system?
$$
\left[ \begin{array} {r} {{{{\dot{x}}_{1}}}} \\ {{{{\dot{x}}_{2}}}} \\ \end{array} \right]=\left[ \begin{array} {r r} {{0}} & {{1}} \\ {{-2}} & {{-3}} \\ \end{array} \right] \left[ \begin{array} {r} {{{x_{1}}}} \\ {{{x_{2}}}} \\ \end{array} \right]+\left[ \begin{array} {r} {{{0}}} \\ {{{1}}} \\ \end{array} \right] u
$$

Options:
A. $$
\left[ \begin{array} {c} {{{x_{1} ( t )}}} \\ {{{x_{2} ( t )}}} \\ \end{array} \right]=\left[ \begin{array} {c} {{{{\frac{1} {3}}+{\mathrm{e}}^{-t}-{\mathrm{e}}^{-3 t}}}} \\ {{{{\mathrm{e}}^{-t}+{\mathrm{e}}^{-3 t}}}} \\ \end{array} \right]
$$
B. $$
\left[ \begin{array} {c} {{{x_{1} ( t )}}} \\ {{{x_{2} ( t )}}} \\ \end{array} \right]=\left[ \begin{array} {c} {{{{\mathrm{e}}^{-t}-{\frac{1} {2}}+{\frac{1} {3}} {\mathrm{e}}^{-3 t}}}} \\ {{{{\mathrm{e}}^{-3 t}+{\mathrm{e}}^{-2 t}}}} \\ \end{array} \right]
$$
C. $$
\left[ \begin{array} {c} {{{x_{1} ( t )}}} \\ {{{x_{2} ( t )}}} \\ \end{array} \right]=\left[ \begin{array} {c} {{{{\mathrm{e}}^{-t}+{\mathrm{e}}^{-2 t}-{\frac{1} {3}}}}} \\ {{{{\mathrm{e}}^{-t}+{\mathrm{e}}^{-2 t}}}} \\ \end{array} \right]
$$
D. $$
\left[ \begin{array} {c} {{{x_{1} ( t )}}} \\ {{{x_{2} ( t )}}} \\ \end{array} \right]=\left[ \begin{array} {c} {{{{\mathrm{e}}^{-2 t}-{\frac{1} {3}}+{\frac{1} {3}} {\mathrm{e}}^{-t}}}} \\ {{{{\mathrm{e}}^{-t}+{\frac{1} {2}} {\mathrm{e}}^{-3 t}}}} \\ \end{array} \right]
$$
E. $$
\left[ \begin{array} {c} {{{x_{1} ( t )}}} \\ {{{x_{2} ( t )}}} \\ \end{array} \right]=\left[ \begin{array} {c} {{{{\mathrm{e}}^{-t}+{\mathrm{e}}^{-2 t}+{\frac{1} {3}}}}} \\ {{{{\mathrm{e}}^{-2 t}-{\mathrm{e}}^{-3 t}}}} \\ \end{array} \right]
$$
F. $$
\left[ \begin{array} {c} {{{x_{1} ( t )}}} \\ {{{x_{2} ( t )}}} \\ \end{array} \right]=\left[ \begin{array} {c} {{{{\frac{1} {3}}+{\mathrm{e}}^{-t}+{\mathrm{e}}^{-3 t}}}} \\ {{{{\mathrm{e}}^{-t}-{\mathrm{e}}^{-3 t}}}} \\ \end{array} \right]
$$
G. $$
\left[ \begin{array} {c} {{{x_{1} ( t )}}} \\ {{{x_{2} ( t )}}} \\ \end{array} \right]=\left[ \begin{array} {c} {{{{\frac{1} {2}}+{\mathrm{e}}^{-2 t}+{\frac{1} {3}} {\mathrm{e}}^{-t}}}} \\ {{{{\mathrm{e}}^{-2 t}-{\mathrm{e}}^{-t}}}} \\ \end{array} \right]
$$
H. $$
\left[ \begin{array} {c} {{{x_{1} ( t )}}} \\ {{{x_{2} ( t )}}} \\ \end{array} \right]=\left[ \begin{array} {c} {{{{\frac{1} {2}}-{\mathrm{e}}^{-t}+{\frac{1} {2}} {\mathrm{e}}^{-2 t}}}} \\ {{{{\mathrm{e}}^{-t}-{\mathrm{e}}^{-2 t}}}} \\ \end{array} \right]
$$
I. $$
\left[ \begin{array} {c} {{{x_{1} ( t )}}} \\ {{{x_{2} ( t )}}} \\ \end{array} \right]=\left[ \begin{array} {c} {{{{\mathrm{e}}^{-3 t}-{\mathrm{e}}^{-t}+{\mathrm{e}}^{-2 t}}}} \\ {{{{\mathrm{e}}^{-t}+{\frac{1} {3}} {\mathrm{e}}^{-3 t}}}} \\ \end{array} \right]
$$
J. $$
\left[ \begin{array} {c} {{{x_{1} ( t )}}} \\ {{{x_{2} ( t )}}} \\ \end{array} \right]=\left[ \begin{array} {c} {{{{\frac{1} {3}}+{\mathrm{e}}^{-t}-{\mathrm{e}}^{-2 t}}}} \\ {{{{\mathrm{e}}^{-3 t}+{\mathrm{e}}^{-t}}}} \\ \end{array} \right]
$$
Answer: H
The element lead (Pb) consists of four naturally occur- ring isotopes with atomic masses 203.97302, 205.97444, 206.97587, and 207.97663 amu. The relative abundances of these four isotopes are 1.4, 24.1, 22.1, and 52.4%, re- spectively. From these data, calculate the atomic weight of lead.

Options:
A. $$
2 0 7 . 5 \, \mathrm{a m u}
$$
B. $$
2 0 7 \, \mathrm{a m u}
$$
C. $$
2 0 4 . 5 \, \mathrm{a m u}
$$
D. $$
2 0 8 \, \mathrm{a m u}
$$
E. $$
2 0 6 . 8 \, \mathrm{a m u}
$$
F. $$
2 0 6 \, \mathrm{a m u}
$$
G. $$
2 0 5 \, \mathrm{a m u}
$$
H. $$
2 0 6 . 5 \, \mathrm{a m u}
$$
I. $$
2 0 8 . 1 \, \mathrm{a m u}
$$
Answer: B
Hydrogen sulfide is an impurity in natural gas that must be removed. One common removal method is called the Claus process, which relies on the reaction:
$$
8 \, \mathrm{H}_{2} \mathrm{S} ( g ) \,+\, 4 \, \mathrm{O}_{2} ( g ) \, \longrightarrow\, \mathrm{S}_{8} ( l ) \,+\, 8 \, \mathrm{H}_{2} \mathrm{O} ( g )
$$
Under optimal conditions the Claus process gives 98% yield of $\mathrm{S_{8}}$ from H2S. If you started with 30.0 grams of H$_{2}$S and 50.0 grams of $\mathrm{O_{2}},$ how many grams of $\mathrm{S_{8}}$ would be produced, assuming 98% yield?

Options:
A. $$
3 8 \operatorname{g} \operatorname{S}_{8} \operatorname{a c t u a l}
$$
B. $$
3 5 \operatorname{g} \operatorname{S}_{8} \operatorname{a c t u a l}
$$
C. $$
3 0 \operatorname{g} \operatorname{S}_{8} \operatorname{a c t u a l}
$$
D. $$
2 4 \operatorname{g} \operatorname{S}_{8} \operatorname{a c t u a l}
$$
E. $$
2 8 \operatorname{g} \operatorname{S}_{8} \operatorname{a c t u a l}
$$
F. $$
2 7 \operatorname{g} \operatorname{S}_{8} \operatorname{a c t u a l}
$$
G. $$
2 2 \operatorname{g} \operatorname{S}_{8} \operatorname{a c t u a l}
$$
H. $$
3 2 \operatorname{g} \operatorname{S}_{8} \operatorname{a c t u a l}
$$
I. $$
2 3 \operatorname{g} \operatorname{S}_{8} \operatorname{a c t u a l}
$$
J. $$
1 8 \operatorname{g} \operatorname{S}_{8} \operatorname{a c t u a l}
$$
Answer: E
The name of the dance performed in "Po Han Hu Xi" is ____.

Options:
A. "The Soul of Guanye"
B. "The Dance of Lingyue"
C. "The Essence of Shaotan"
D. "The Legacy of Huaxu"
E. "The Spirit of Yuantao"
F. "The Grace of Tianhua"
G. "The Motion of Fengrao"
H. "The Dawn of Fuxing"
I. "The Art of Huantuo"
J. "The Power of Lantian"
Answer: I
Keep the pressure at $p^{\Theta}$, and when a definite quantity of iodine dissolves in the $\mathrm{H}_{2} \mathrm{O} \cdot \mathrm{CCl}_{4}$ system without forming solid $\mathrm{I}_{2}$, what is the number of degrees of freedom of the equilibrium system?

Options:
A. f=9
B. f=8
C. f=6
D. f=1
E. f=3
F. f=7
G. f=5
H. f=4
I. f=0
J. f=2
Answer: D
Calculate the fugacity and fugacity coefficient of the gas with a density of $\rho = 161.4g•dm^{-3}$ at $373K$ and $100p^{\Theta}$ ethane (g).

Options:
A. $$
\begin{array} {l} {{{\gamma=0. 5 8 9 9}}} \\ {{{f=5 8 9 9 \, \mathrm{k P a}}}} \\ \end{array}
$$
B. $$
\begin{array} {l} {\gamma=0.6083} \\ {f=6083 kPa} \\ \end{array}
$$
C. $$
\begin{array} {l} {{{\gamma=0. 6 4 2 0}}} \\ {{{f=6 4 2 0 \, \mathrm{k P a}}}} \\ \end{array}
$$
D. $$
\begin{array} {l} {{{\gamma=0. 6 2 1 5}}} \\ {{{f=6 2 1 5 \, \mathrm{k P a}}}} \\ \end{array}
$$
E. $$
\begin{array} {l} {{{\gamma=0. 6 1 5 7}}} \\ {{{f=6 1 5 7 \, \mathrm{k P a}}}} \\ \end{array}
$$
F. $$
\begin{array} {l} {{{\gamma=0. 7 0 0 0}}} \\ {{{f=7 0 0 0 \, \mathrm{k P a}}}} \\ \end{array}
$$
G. $$
\begin{array} {l} {{{\gamma=0. 5 6 7 8}}} \\ {{{f=5 6 7 8 \, \mathrm{k P a}}}} \\ \end{array}
$$
H. $$
\begin{array} {l} {{{\gamma=0. 5 9 8 2}}} \\ {{{f=5 9 8 2 \, \mathrm{k P a}}}} \\ \end{array}
$$
I. $$
\begin{array} {l} {{{\gamma=0. 6 3 9 4}}} \\ {{{f=6 3 9 4 \, \mathrm{k P a}}}} \\ \end{array}
$$
J. $$
\begin{array} {l} {{{\gamma=0. 5 7 3 6}}} \\ {{{f=5 7 3 6 \, \mathrm{k P a}}}} \\ \end{array}
$$
Answer: B
Solve for the $K_{p}^{\Theta}$ of the reaction $Na (g) = Na^{+} (g) + e^{-} (g)$ at $500K$, given the following data:
Molar mass of sodium: $M (Na) = 22.99 g/mol$, $m(e^{-}) = 9.111 \times 10^{-31} kg$,
The total angular momentum quantum number $J = 1/2$ of the electronic ground state of Na (g),
the first ionization potential of Na is $5.14 eV (1 eV = 1.602 \times 10^{-19} J$).
Assume sodium's higher electronic excited states are negligible, and the free electron can be treated as an ideal gas. The electronic degeneracy is $q_{e,\theta} = 2$. What is the value of $K_{p}^{\Theta}$?

Options:
A. $$
8. 1 7 \times1 0^{-4}
$$
B. $$
3. 8 2 \times1 0^{-3}
$$
C. $$
6. 8 4 \times1 0^{-3}
$$
D. $$
2. 6 9 \times1 0^{-4}
$$
E. $$
4. 7 5 \times1 0^{-2}
$$
F. $$
9. 0 1 \times1 0^{-6}
$$
G. $$
2. 5 8 \times1 0^{-3}
$$
H. $$
1. 2 3 \times1 0^{-5}
$$
I. $$
7. 3 5 \times1 0^{-2}
$$
J. $$
5. 1 0 \times1 0^{-1}
$$
Answer: B
The experiment determined that, under constant pressure, the rate constant for the gas-phase bimolecular isomerization reaction of cis-ethylene-$d_2$ catalyzed by NO follows the relationship:
$k =2.28 \times 10^{8} exp (-116.65 \times 10^{3} J \cdot mol^{-1} / RT) mol^{-1} \cdot \, dm^{3} \cdot s^{-1}$
What is the standard activation entropy $\Delta_{r}^{≠} S_{m}^{\theta} (600 K)$ for this reaction at the standard state $p^{\theta} = 101.325 kPa$?

Options:
A. $-78. 5$ $J\cdot K^{- 1}\cdot \mathrm{mol}^{-1}$
B. $-83. 1$ $J\cdot K^{- 1}\cdot \mathrm{mol}^{-1}$
C. $-76. 8$ $J\cdot K^{- 1}\cdot \mathrm{mol}^{-1}$
D. $-82. 1$ $J\cdot K^{- 1}\cdot \mathrm{mol}^{-1}$
E. $-87. 9$ $J\cdot K^{- 1}\cdot \mathrm{mol}^{-1}$
F. $-65. 4$ $J\cdot K^{- 1}\cdot \mathrm{mol}^{-1}$
G. $-70. 2$ $J\cdot K^{- 1}\cdot \mathrm{mol}^{-1}$
H. $-72. 3$ $J\cdot K^{- 1}\cdot \mathrm{mol}^{-1}$
I. $-94. 6$ $J\cdot K^{- 1}\cdot \mathrm{mol}^{-1}$
J. $-91. 7$ $J\cdot K^{- 1}\cdot \mathrm{mol}^{-1}$
Answer: B
Given the solution reaction $S_2O_8^{2-}(aq) + 2I^−({aq}^{-}) = 2SO_4^{2-}(aq) + I_2(aq)$, the experimentally determined reaction rate constant is $k_0 = 1.38 \times 10^{-3} mol^{-1} \cdot dm^3 \cdot s^{-1}$. Now, if $c(KI) = 0.0100 mol \cdot kg^{-1}$ and $c(Na_2S_2O_8) = 1.5 \times 10^{-1} mol\cdot kg^{-1}$ are mixed, what is the reaction rate constant $k_d$ for this reaction at 298 K?

Options:
A. $$
1. 8 7 \times1 0^{-3} \mathrm{~ m o l}^{-1} \cdot\mathrm{d m}^{3} \cdot\mathrm{s}^{-1}
$$
B. $$
2. 9 2 \times1 0^{-3} \mathrm{~ m o l}^{-1} \cdot\mathrm{d m}^{3} \cdot\mathrm{s}^{-1}
$$
C. $$
1. 2 9 \times1 0^{-3} \mathrm{~ m o l}^{-1} \cdot\mathrm{d m}^{3} \cdot\mathrm{s}^{-1}
$$
D. $$
2. 2 3 \times1 0^{-3} \mathrm{~ m o l}^{-1} \cdot\mathrm{d m}^{3} \cdot\mathrm{s}^{-1}
$$
E. $$
3. 4 1 \times1 0^{-3} \mathrm{~ m o l}^{-1} \cdot\mathrm{d m}^{3} \cdot\mathrm{s}^{-1}
$$
F. $$
3. 0 9 \times1 0^{-3} \mathrm{~ m o l}^{-1} \cdot\mathrm{d m}^{3} \cdot\mathrm{s}^{-1}
$$
G. $$
2. 7 4 \times1 0^{-3} \mathrm{~ m o l}^{-1} \cdot\mathrm{d m}^{3} \cdot\mathrm{s}^{-1}
$$
H. $$
1. 5 6 \times1 0^{-3} \mathrm{~ m o l}^{-1} \cdot\mathrm{d m}^{3} \cdot\mathrm{s}^{-1}
$$
I. $$
3. 8 0 \times1 0^{-3} \mathrm{~ m o l}^{-1} \cdot\mathrm{d m}^{3} \cdot\mathrm{s}^{-1}
$$
J. $$
1. 6 4 \times1 0^{-3} \mathrm{~ m o l}^{-1} \cdot\mathrm{d m}^{3} \cdot\mathrm{s}^{-1}
$$
Answer: D
At 298 K, $2.34 \times 10^{-4}$ kg of NaCl is added to 1 $dm^3$ of $5.00 \times 10^{-3} mol \cdot dm^{-3}$ HCl solution. If the change in the solution volume is neglected, what is the change in the solution's pH?

Options:
A. -2.01
B. 2.20
C. 2.00
D. 2.03
E. 2.15
F. 2.34
G. -32.02
H. 3.10
I. 3.02
J. 2.05
Answer: F
The $\Lambda_m$ of a dilute strong electrolyte solution follows the Onsager conductivity equation in relation to c:
$$\Lambda_{m} = \Lambda_{m}^{\infty} - (a\Lambda_{m}^{\infty} + b) c^{1/2}$$
where the unit of c is $mol \cdot m^{-3}$, and a and b are constants at a fixed temperature and solvent. For an aqueous solution at 298 K,
$a = 7.273 \times 10^{-3} m^{3/2}\cdot mol^{-1/2}$, $b = 1.918 \times 10^{-4} m^{7/2}\cdot mol^{-3/2}$. Given that $U^\infty(Na^+) = 5.2 \times 10^{-3}$ m$^{2}\cdot V^{- 1}\cdot s^{- 1}$ and $U^\infty(Cl^-) = 7.9 \times 10^{-3}$ m$^{2}\cdot V^{- 1}\cdot s^{- 1}$.
$t(Na^+) \approx 0.394$ in a 0.00319 $mol \cdot dm^{-3}$ NaCl aqueous solution.Calculate $U(Na^+)$ and $U(Cl^-)$.

Options:
A. $$
4. 7 9 \times 1 0^{-3} \mathrm{~ m}^{2} \cdot\mathrm{~ V}^{-1} \cdot\mathrm{~ s}^{-1}
$$
$$
7. 6 0 \times 1 0^{-3} \, \mathrm{m}^{2} \cdot\mathrm{V}^{-1} \cdot\mathrm{s}^{-1}
$$
B. $$
4. 9 2 \times 1 0^{-3} \mathrm{~ m}^{2} \cdot\mathrm{~ V}^{-1} \cdot\mathrm{~ s}^{-1}
$$
$$
7. 6 5 \times 1 0^{-3} \, \mathrm{m}^{2} \cdot\mathrm{V}^{-1} \cdot\mathrm{s}^{-1}
$$
C. $$
4. 9 0 \times 1 0^{-3} \mathrm{~ m}^{2} \cdot\mathrm{~ V}^{-1} \cdot\mathrm{~ s}^{-1}
$$
$$
7. 6 8 \times 1 0^{-3} \, \mathrm{m}^{2} \cdot\mathrm{V}^{-1} \cdot\mathrm{s}^{-1}
$$
D. $$
5. 0 0 \times 1 0^{-3} \mathrm{~ m}^{2} \cdot\mathrm{~ V}^{-1} \cdot\mathrm{~ s}^{-1}
$$
$$
7. 7 3 \times 1 0^{-3} \, \mathrm{m}^{2} \cdot\mathrm{V}^{-1} \cdot\mathrm{s}^{-1}
$$
E. $$
4. 8 5 \times 1 0^{-3} \mathrm{~ m}^{2} \cdot\mathrm{~ V}^{-1} \cdot\mathrm{~ s}^{-1}
$$
$$
7. 5 8 \times 1 0^{-3} \, \mathrm{m}^{2} \cdot\mathrm{V}^{-1} \cdot\mathrm{s}^{-1}
$$
F. $$
5. 0 8 \times 1 0^{-3} \mathrm{~ m}^{2} \cdot\mathrm{~ V}^{-1} \cdot\mathrm{~ s}^{-1}
$$
$$
7. 7 0 \times 1 0^{-3} \, \mathrm{m}^{2} \cdot\mathrm{V}^{-1} \cdot\mathrm{s}^{-1}
$$
G. $$
5. 0 2 \times 1 0^{-3} \mathrm{~ m}^{2} \cdot\mathrm{~ V}^{-1} \cdot\mathrm{~ s}^{-1}
$$
$$
7. 8 0 \times 1 0^{-3} \, \mathrm{m}^{2} \cdot\mathrm{V}^{-1} \cdot\mathrm{s}^{-1}
$$
H. $$
5. 1 0 \times 1 0^{-3} \mathrm{~ m}^{2} \cdot\mathrm{~ V}^{-1} \cdot\mathrm{~ s}^{-1}
$$
$$
7. 7 5 \times 1 0^{-3} \, \mathrm{m}^{2} \cdot\mathrm{V}^{-1} \cdot\mathrm{s}^{-1}
$$
I. $$
4. 9 5 \times1 0^{-3} \mathrm{~ m}^{2} \cdot\mathrm{~ V}^{-1} \cdot\mathrm{~ s}^{-1}
$$
$$
7. 6 2 \times1 0^{-3} \, \mathrm{m}^{2} \cdot\mathrm{V}^{-1} \cdot\mathrm{s}^{-1}
$$
J. $$
4. 8 8 \times 1 0^{-3} \mathrm{~ m}^{2} \cdot\mathrm{~ V}^{-1} \cdot\mathrm{~ s}^{-1}
$$
$$
7. 5 4 \times 1 0^{-3} \, \mathrm{m}^{2} \cdot\mathrm{V}^{-1} \cdot\mathrm{s}^{-1}
$$
Answer: I
At 298K, the electromotive force of the following cell is measured to be 0.200 V.
$$
Pt, H_{2} (p^{\Theta}) | HBr (0.100 mol \cdot kg^{-1}) | AgBr (s) | Ag
$$
$\phi^{\Theta} (\mathrm{Br}^{-} \mid \mathrm{AgBr} \mid \mathrm{Ag}) = 0.071 \mathrm{V}$. Write the electrode reactions and the cell reaction, and determine the mean activity coefficient of HBr at the specified concentration.

Options:
A. 0.789
B. 0.674
C. 0.881
D. 0.732
E. 0.856
F. 0.923
G. 0.741
H. 0.597
I. 0.812
J. 0.648
Answer: I
Consider a rocket engine burning hydrogen and oxygen. The total mass flow of the propellant plus oxidizer into the combustion chamber is
287.2 kg/s. The combustion chamber temperature is 3600 K. Assume that the combustion chamber is a low-velocity reservoir for the rocket engine. If the area of the rocket nozzle throat is 0.2 $\mathrm{m}^{2}$ , calculate the combustion chamber (reservoir) pressure is (). Assume that the gas that flows through the engine has a ratio of specific heats, $\gamma=1. 2$ , and a molecular weight of 16.

Options:
A. $$
{2 7 \mathrm{~ a t m}}
$$
B. $$
{3 8 \mathrm{~ a t m}}
$$
C. $$
{2 8 \mathrm{~ a t m}}
$$
D. $$
{3 5 \mathrm{~ a t m}}
$$
E. $$
{3 2 \mathrm{~ a t m}}
$$
F. $$
{2 0 \mathrm{~ a t m}}
$$
G. $$
{4 0 \mathrm{~ a t m}}
$$
H. $$
{2 5 \mathrm{~ a t m}}
$$
I. $$
{3 0 \mathrm{~ a t m}}
$$
J. $$
{4 5 \mathrm{~ a t m}}
$$
Answer: I
Sap flows up a tree at a speed of about $1$ mm $s^{-1}$ through its vascular system (xylem), which consists of cylindrical pores of 20 $\mu m$ radius. Assume the viscosity of sap is the same as the viscosity of water. What pressure difference between the bottom and top of a 100 m tall tree is needed to generate this flow? How does it compare to the hydrostatic pressure difference caused by gravity?

Options:
A. $$
3 2 \mathrm{a t m}
$$
$$
1 6 \mathrm{a t m}
$$
B. $$
2 0 \mathrm{a t m}
$$
$$
1 2 \mathrm{a t m}
$$
C. $$
2 2 \mathrm{a t m}
$$
$$
1 3 \mathrm{a t m}
$$
D. $$
2 7 \mathrm{a t m}
$$
$$
1 4 \mathrm{a t m}
$$
E. $$
2 5 \mathrm{a t m}
$$
$$
1 5 \mathrm{a t m}
$$
F. $$
1 5 \mathrm{a t m}
$$
$$
1 2 \mathrm{a t m}
$$
G. $$
1 8 \mathrm{a t m}
$$
$$
1 0 \mathrm{a t m}
$$
H. $$
3 5 \mathrm{a t m}
$$
$$
2 0 \mathrm{a t m}
$$
I. $$
3 0 \mathrm{a t m}
$$
$$
1 8 \mathrm{a t m}
$$
J. $$
2 0 \mathrm{a t m}
$$
$$
1 0 \mathrm{a t m}
$$
Answer: J
A sound wave moving through water has a frequency of 256 Hz and a wavelength of 5.77 m. What is the speed of the wave?

Options:
A. $$
\mathrm{1 4 9 0 ~ m / s.}
$$
B. $$
\mathrm{1 4 8 0 ~ m / s.}
$$
C. $$
\mathrm{1 4 4 5 ~ m / s.}
$$
D. $$
\mathrm{1 3 9 5 ~ m / s.}
$$
E. $$
\mathrm{1 5 3 0 ~ m / s.}
$$
F. $$
\mathrm{1 5 0 0 ~ m / s.}
$$
G. $$
\mathrm{1 4 7 0 ~ m / s.}
$$
H. $$
\mathrm{1 4 2 0 ~ m / s.}
$$
I. $$
\mathrm{1 4 8 5 ~ m / s.}
$$
J. $$
\mathrm{1 4 6 0 ~ m / s.}
$$
Answer: B
Which of the following is not evidence for supernovae in our Galaxy?

Options:
A. The study of historical records of stellar explosions
B. The identification of gamma-ray bursts in nearby galaxies
C. The discovery of pulsar wind nebulae
D. The measurement of cosmic ray isotopes
E. The analysis of ancient meteorites' isotopic makeup
F. The observation of supernova remnants like Cassiopeia A
G. The formation of heavy elements like gold
H. The existence of binary stars in our Galaxy
I. The observation of radioactive isotopes in interstellar space
J. The detection of neutrinos from a supernova event
Answer: H
A coffee-cup calorimeter of the type contains 150.0 g
of water at 25.1 °C. A 121.0-g block of copper metal is heated to 100.4 °C by putting it in a beaker of boiling water. The specific heat of $\mathrm{C u} ( s )$ is $0. 3 8 5 J / \mathrm{g·K}$ The Cu is added to the calorimeter, and after a time the contents of the cup reach a constant temperature of 30.1°C.The difference is due to heat loss through the Styrofoam cups and the heat necessary to raise the temperature of the inner wall of the apparatus. The heat capacity of the calorimeter is the amount of heat necessary to raise the temperature of the apparatus (the cups and the stopper) by 1 K. Calculate the heat capacity of the calorimeter in J/K.

Options:
A. $$
4 \times1 0 \, \mathrm{J / K}.
$$
B. $$
9 \times1 0 \, \mathrm{J / K}.
$$
C. $$
3 \times1 0 \, \mathrm{J / K}.
$$
D. $$
8 \times1 0 \, \mathrm{J / K}.
$$
E. $$
6 \times1 0 \, \mathrm{J / K}.
$$
F. $$
1 \times1 0 \, \mathrm{J / K}.
$$
G. $$
2 \times1 0 \, \mathrm{J / K}.
$$
H. $$
0 \times1 0 \, \mathrm{J / K}.
$$
I. $$
5 \times1 0 \, \mathrm{J / K}.
$$
J. $$
7 \times1 0 \, \mathrm{J / K}.
$$
Answer: A
Adopt as a detection criterion$\phi_{\mathrm{e f f}} \sigma( E ) \geq3 \langle\phi\sigma\rangle$ . Here $\sigma( E )$ is the capture cross
$(=2. 7 \times1 0^{-4 2}$ cm$^{2}$ per$^{37}$Cl atom at 10 MeV), while $\langle\phi\sigma\rangle$ is the average capture rate for solar neutrinos which the experiment is designed to detect. For this we may use the measured value of $\langle\phi\sigma\rangle$ , which is ~ 2 SNU (1 SNU =10 $^{-36}$ captures per atom per second). Out to what value of $R$ is the experiment able to detect a supernova?

Options:
A. $$
R \sim6 \mathrm{~ k p c}
$$
B. $$
R \sim1 \mathrm{~ k p c}
$$
C. $$
R \sim7 \mathrm{~ k p c}
$$
D. $$
R \sim5 \mathrm{~ k p c}
$$
E. $$
R \sim0.2 \mathrm{~ k p c}
$$
F. $$
R \sim3 \mathrm{~ k p c}
$$
G. $$
R \sim0.5 \mathrm{~ k p c}
$$
H. $$
R \sim4 \mathrm{~ k p c}
$$
I. $$
R \sim2 \mathrm{~ k p c}
$$
J. $$
R \sim8 \mathrm{~ k p c}
$$
Answer: H
Assume that the accreting gas possesses an equipartition magnetic field, where
$$
\frac{B^{2}} {8 \pi} \, \sim\, \frac{G M \rho} {r}
$$
Such a field might arise if everywhere the growth of a frozen-in, tangled field threading the infalling plasma were limited by the magnetic reconnection of oppositely directed, radial field lines (Shvarstman, 1971; Shapiro, 1973b). Reconnection timescales are given by $t_{\mathrm{r e c o n}} \sim r / v_{\mathrm{A}}$ , where $v_{\mathrm{A}}( B^{2} / 8 \pi\rho)^{1 / 2}$ is the Alfven velocity or magnetic "sound speed.' The amplification of the $B$ field is limited by the condition $t_{\mathrm{r e c o n}} \sim t_{\mathrm{f r e e-f a l l}}$ , where $t_{\mathrm{f r e e-f a l l}}/simr / ( G M / r )^{1 / 2}$ is the infall time. This condition gives Eq.Estimate the synchrotron luminosity is(), $L_{\mathrm{s y n}}$ resulting from relativistic electrons gyrating around equipartition feld lines.

Options:
A. $$
L_{\mathrm{s y n}} \sim1 0^{2 4} ( n_{\infty} / 1 \ \mathrm{c m}^{-3} )^{2} ( T_{\infty} / 1 0^{4} \ \mathrm{K} )^{-4} ( M / M_{\odot} )^{1} \ \mathrm{e r g \ s}^{-1}
$$
B. $$
L_{\mathrm{s y n}} \sim1 0^{2 7} ( n_{\infty} / 1 \ \mathrm{c m}^{-3} )^{2} ( T_{\infty} / 1 0^{4} \ \mathrm{K} )^{-2} ( M / M_{\odot} )^{4} \ \mathrm{e r g \ s}^{-1}
$$
C. $$
L_{\mathrm{s y n}} \sim1 0^{2 3} ( n_{\infty} / 1 \ \mathrm{c m}^{-3} )^{1} ( T_{\infty} / 1 0^{4} \ \mathrm{K} )^{-4} ( M / M_{\odot} )^{3} \ \mathrm{e r g \ s}^{-1}
$$
D. $$
L_{\mathrm{s y n}} \sim1 0^{2 6} ( n_{\infty} / 1 \ \mathrm{c m}^{-3} )^{1} ( T_{\infty} / 1 0^{4} \ \mathrm{K} )^{-5} ( M / M_{\odot} )^{3} \ \mathrm{e r g \ s}^{-1}
$$
E. $$
L_{\mathrm{s y n}} \sim1 0^{2 5} ( n_{\infty} / 1 \ \mathrm{c m}^{-3} )^{2} ( T_{\infty} / 1 0^{4} \ \mathrm{K} )^{-3} ( M / M_{\odot} )^{2} \ \mathrm{e r g \ s}^{-1}
$$
F. $$
L_{\mathrm{s y n}} \sim1 0^{2 7} ( n_{\infty} / 1 \ \mathrm{c m}^{-3} )^{2} ( T_{\infty} / 1 0^{4} \ \mathrm{K} )^{-3} ( M / M_{\odot} )^{3} \ \mathrm{e r g \ s}^{-1}
$$
G. $$
L_{\mathrm{s y n}} \sim1 0^{2 9} ( n_{\infty} / 1 \ \mathrm{c m}^{-3} )^{2} ( T_{\infty} / 1 0^{4} \ \mathrm{K} )^{-1} ( M / M_{\odot} )^{2} \ \mathrm{e r g \ s}^{-1}
$$
H. $$
L_{\mathrm{s y n}} \sim1 0^{3 1} ( n_{\infty} / 1 \ \mathrm{c m}^{-3} )^{4} ( T_{\infty} / 1 0^{4} \ \mathrm{K} )^{-3} ( M / M_{\odot} )^{2} \ \mathrm{e r g \ s}^{-1}
$$
I. $$
L_{\mathrm{s y n}} \sim1 0^{3 0} ( n_{\infty} / 1 \ \mathrm{c m}^{-3} )^{3} ( T_{\infty} / 1 0^{4} \ \mathrm{K} )^{-2} ( M / M_{\odot} )^{2} \ \mathrm{e r g \ s}^{-1}
$$
J. $$
L_{\mathrm{s y n}} \sim1 0^{2 8} ( n_{\infty} / 1 \ \mathrm{c m}^{-3} )^{3} ( T_{\infty} / 1 0^{4} \ \mathrm{K} )^{-4} ( M / M_{\odot} )^{3} \ \mathrm{e r g \ s}^{-1}
$$
Answer: F
Although the gradient, divergence, and curl theorems are the fundamental in- tegral theorems of vector calculus, it is possible to derive a number of corollaries from them. Show that:$\int_{\mathcal{V}} ( \nabla T ) \, d \tau\,=\, \oint_{\mathcal{S}} T \, d \mathbf{a}$ .

Options:
A. $$
\int T \, d \mathbf{V}.
$$
B. $$
\int \nabla T \, d \mathbf{s}.
$$
C. $$
\int \nabla T \, d \mathbf{V}.
$$
D. $$
\int T \, d \nabla.
$$
E. $$
\oint \nabla T \, d \mathbf{a}.
$$
F. $$
\oint \nabla T \, d \nabla.
$$
G. $$
\oint T \, d \mathbf{V}.
$$
H. $$
\int \nabla T \, d \mathbf{a}.
$$
I. $$
\oint T \, d \nabla.
$$
J. $$
\int T \, d \mathbf{a}.
$$
Answer: J
A certain first-order reaction has a rate constant of $2. 7 5 \times1 0^{-2} \, \mathrm{s}^{-1}$ at $2 0 \, {}^{\circ}{C}$ .What is the value of $k$ at $60 °C$ if $E_{a}=1 2 5 \, \mathrm{k J / m o l?}$

Options:
A. $$ 1. 5 7 \, \mathrm{k J / m o l} $$
B. $$ 1. 5 9 \, \mathrm{k J / m o l} $$
C. $$ 2. 3 9 \, \mathrm{k J / m o l} $$
D. $$ 2. 7 8 \, \mathrm{k J / m o l} $$
E. $$ 1. 6 5 \, \mathrm{k J / m o l} $$
F. $$ 2. 0 5 \, \mathrm{k J / m o l} $$
G. $$ 1. 8 4 \, \mathrm{k J / m o l} $$
H. $$ 1. 3 2 \, \mathrm{k J / m o l} $$
I. $$ 2. 4 1 \, \mathrm{k J / m o l} $$
J. $$
1. 1 5 \, \mathrm{k J / m o l}
$$
Answer: J
The mass of octane, $C_{8}H_{18}(l)$ is______, that must be burned in air to evolve the same quantity of energy as produced by the fusion of $1. 0 \ \mathrm{g}$ of hydrogen in the fol- lowing fusion reaction:
$$
4^{1}_{1} \longrightarrow\mathrm{^{4}_{2}He}+2^{0}_{1}{e}
$$
Assume that all the products of the combustion of octane are in their gas phases. The stan- dard enthalpy of formation of octane is 250.1 kJ/mol.

Options:
A. $$ 4. 7 \, \times\, 1 0^{4} \mathrm{~ k g ~ C_{8} H_{1 8} ~} $$
B. $$ 5. 4 \, \times\, 1 0^{4} \mathrm{~ k g ~ C_{8} H_{1 8} ~} $$
C. $$ 2. 2 \, \times\, 1 0^{5} \mathrm{~ k g ~ C_{8} H_{1 8} ~} $$
D. $$ 2. 5 \, \times\, 1 0^{3} \mathrm{~ k g ~ C_{8} H_{1 8} ~} $$
E. $$
1. 4 \, \times\, 1 0^{4} \mathrm{~ k g ~ C_{8} H_{1 8} ~}
$$
F. $$ 9. 9 \, \times\, 1 0^{3} \mathrm{~ k g ~ C_{8} H_{1 8} ~} $$
G. $$ 3. 1 \, \times\, 1 0^{5} \mathrm{~ k g ~ C_{8} H_{1 8} ~} $$
H. $$ 8. 6 \, \times\, 1 0^{2} \mathrm{~ k g ~ C_{8} H_{1 8} ~} $$
I. $$ 7. 3 \, \times\, 1 0^{2} \mathrm{~ k g ~ C_{8} H_{1 8} ~} $$
J. $$ 6. 8 \, \times\, 1 0^{3} \mathrm{~ k g ~ C_{8} H_{1 8} ~} $$
Answer: E
lf the pH of a 1.0-in. rainfall over 1500 $mi^{2}$ is 3.5, how
many kilograms of $H_{2}SO_{4}$ are present, assuming that it
is the only acid contributing to the pH?

Options:
A. $$
5 \, \times\, 1 0^{5} \, \mathrm{k g \, H}_{2} \mathrm{S O}_{4}
$$
B. $$
7 \, \times\, 1 0^{6} \, \mathrm{k g \, H}_{2} \mathrm{S O}_{4}
$$
C. $$
8 \, \times\, 1 0^{6} \, \mathrm{k g \, H}_{2} \mathrm{S O}_{4}
$$
D. $$
4 \, \times\, 1 0^{7} \, \mathrm{k g \, H}_{2} \mathrm{S O}_{4}
$$
E. $$
3 \, \times\, 1 0^{6} \, \mathrm{k g \, H}_{2} \mathrm{S O}_{4}
$$
F. $$
1 \, \times\, 1 0^{5} \, \mathrm{k g \, H}_{2} \mathrm{S O}_{4}
$$
G. $$
9 \, \times\, 1 0^{5} \, \mathrm{k g \, H}_{2} \mathrm{S O}_{4}
$$
H. $$
3 \, \times\, 1 0^{4} \, \mathrm{k g \, H}_{2} \mathrm{S O}_{4}
$$
I. $$
2 \, \times\, 1 0^{6} \, \mathrm{k g \, H}_{2} \mathrm{S O}_{4}
$$
J. $$
6 \, \times\, 1 0^{5} \, \mathrm{k g \, H}_{2} \mathrm{S O}_{4}
$$
Answer: I
$\mathsf{A}$ sample of water vapour at 2000C is compressed isothermally from 350 cm to 120 cm3. What is the change in its molar Gibbs energy?

Options:
A. $$
- 2. 6 ~ \mathrm{k J ~ m o l}^{-1}
$$
B. $$
+ 5. 3 ~ \mathrm{k J ~ m o l}^{-1}
$$
C. $$
+ 6. 4 ~ \mathrm{k J ~ m o l}^{-1}
$$
D. $$
- 4. 2 ~ \mathrm{k J ~ m o l}^{-1}
$$
E. $$
+ 7. 0 ~ \mathrm{k J ~ m o l}^{-1}
$$
F. $$
+ 2. 8 ~ \mathrm{k J ~ m o l}^{-1}
$$
G. $$
- 3. 9 ~ \mathrm{k J ~ m o l}^{-1}
$$
H. $$
- 6. 1 ~ \mathrm{k J ~ m o l}^{-1}
$$
I. $$
+ 4. 2 ~ \mathrm{k J ~ m o l}^{-1}
$$
J. $$
+ 3. 7 ~ \mathrm{k J ~ m o l}^{-1}
$$
Answer: I
The mole fractions of $\mathrm{N_{2}}$ and $\mathrm{O_{2}}$ in air at sea level are approximately 0.78 and 0.21, respectively. The molalities of the solution formed in an open flask of water at 25°C is ().

Options:
A. $$
0.48mmolkg;0.23mmolkg
$$
B. $$
0.47mmolkg;0.24mmolkg
$$
C. $$
0.55mmolkg;0.20mmolkg
$$
D. $$
0.60mmolkg;0.30mmolkg
$$
E. $$
0.53mmolkg;0.28mmolkg
$$
F. $$
0.52mmolkg;0.22mmolkg
$$
G. $$
0.50mmolkg;0.27mmolkg
$$
H. $$
0.49mmolkg;0.29mmolkg
$$
I. $$
0.45mmolkg;0.25mmolkg
$$
J. $$
0.40mmolkg;0.26mmolkg
$$
Answer: G
The standard Gibbs energy for the hydrolysis of ATP to ADP is -30.5 kJ mol$^{-1}$; what is the Gibbs energy of reaction in an environment at 37°C in which the ATP, ADP, and $P_{i}$ concentrations are all1.0 mmol dm$^{-3}$?

Options:
A. $$
- 4 6. 2 \mathrm{~ k J ~ m o l}^{-1}
$$
B. $$
- 4 7. 9 \mathrm{~ k J ~ m o l}^{-1}
$$
C. $$
- 5 2. 1 \mathrm{~ k J ~ m o l}^{-1}
$$
D. $$
- 4 5. 6 \mathrm{~ k J ~ m o l}^{-1}
$$
E. $$
- 4 9. 4 \mathrm{~ k J ~ m o l}^{-1}
$$
F. $$
- 5 3. 8 \mathrm{~ k J ~ m o l}^{-1}
$$
G. $$
- 5 1. 3 \mathrm{~ k J ~ m o l}^{-1}
$$
H. $$
- 4 8. 3 \mathrm{~ k J ~ m o l}^{-1}
$$
I. $$
- 5 0. 7 \mathrm{~ k J ~ m o l}^{-1}
$$
J. $$
- 4 4. 1 \mathrm{~ k J ~ m o l}^{-1}
$$
Answer: H
The dissociation vapour pressure (the pressure of gaseous products in equilibrium with the solid reactant) of NH,CI at 427C is 608 kPa but at 459°C it has risen to 1115 kPa. Calculate the equilibrium constant.

Options:
A. $$
{6. 9 1}
$$
$$
{4 7. 2 3}
$$
B. $$
{9. 8 3}
$$
$$
{2 1. 6 8}
$$
C. $$
{2. 0 7}
$$
$$
{6 3. 4 5}
$$
D. $$
{5. 4 3}
$$
$$
{1 2. 8 7}
$$
E. $$
{3. 2 9}
$$
$$
{5 4. 7 1}
$$
F. $$
{8. 7 5}
$$
$$
{2 9. 5 2}
$$
G. $$
{1. 5 6}
$$
$$
{9 9. 8 2}
$$
H. $$
{9. 2 4}
$$
$$
{3 1. 0 8}
$$
I. $$
{4. 8 5}
$$
$$
{3 8. 6 9}
$$
J. $$
{7. 1 6}
$$
$$
{3 5. 0 4}
$$
Answer: H
The solubility of mercury(l) iodide is 5.5 fmol dm$^{-3}$ ( 1 fmol $= 1 0^{-1 5}$ mol) in water at 25°C. What is the standard Gibbs energy of dissolution of the salt?

Options:
A. $$
161 k J m o r^{-1}
$$
B. $$
165 k J m o r^{-1}
$$
C. $$
140 k J m o r^{-1}
$$
D. $$
200 k J m o r^{-1}
$$
E. $$
150 k J m o r^{-1}
$$
F. $$
180 k J m o r^{-1}
$$
G. $$
205 k J m o r^{-1}
$$
H. $$
190 k J m o r^{-1}
$$
I. $$
175 k J m o r^{-1}
$$
J. $$
210 k J m o r^{-1}
$$
Answer: A
Consider a hydrogen electrode in HBr(aq) at 25°C operating at 1.45 bar. Estimate the change in the electrode potential when the solution is changed from 5.0 mmol dm$^{-3}$ to 15.0 mmol dm$^{-3}$ .

Options:
A. $$
7 2 \ \mathrm{m V}
$$
B. $$
4 1 \ \mathrm{m V}
$$
C. $$
9 0 \ \mathrm{m V}
$$
D. $$
3 5 \ \mathrm{m V}
$$
E. $$
2 8 \ \mathrm{m V}
$$
F. $$
6 4 \ \mathrm{m V}
$$
G. $$
8 3 \ \mathrm{m V}
$$
H. $$
1 9 \ \mathrm{m V}
$$
I. $$
4 8 \ \mathrm{m V}
$$
J. $$
5 6 \ \mathrm{m V}
$$
Answer: E
How many kilograms of nickel must be added to 1.75 kg of copper to yield a liquidus temperature of $1300^{°}$C?

Options:
A. $$ 3. 8 0 \ \mathrm{kg} $$
B. $$ 0. 5 9 \ \mathrm{kg} $$
C. $$ 0. 9 7 \ \mathrm{kg} $$
D. $$ 3. 1 8 \ \mathrm{kg} $$
E. $$
1. 3 2 \ \mathrm{k g}
$$
F. $$ 2. 0 4 \ \mathrm{kg} $$
G. $$ 2. 4 5 \ \mathrm{kg} $$
H. $$ 1. 8 9 \ \mathrm{kg} $$
I. $$ 2. 7 3 \ \mathrm{kg} $$
J. $$ 4. 5 6 \ \mathrm{kg} $$
Answer: E
The mass fractions of liquid in the following fireclay refractory materials at $1600^oC$ (2910*F):
25 wt% Al2O3-75 wt% SiO2.

Options:
A. 0.67
B. 0.74
C. 0.79
D. 0.81
E. 0.78
F. 0.82
G. 0.76
H. 0.73
I. 0.71
J. 0.84
Answer: H
The unit '1 millimetre of mercury' (1 mmHg) has been replaced by the unit 1 torr (1 Torr): 1 mmHg is defined as the pressure at the base of a column of mercury exactly 1 mm high when its density is 13.5951 g cm-3 and the acceleration of free fall is 9.806 65 m $\mathrm{s}^{-2}$ What is the relation between the two units?

Options:
A. differ by as much as 2 parts in 10 $^{6}$
B. differ by as much as 5 parts in 10 $^{6}$
C. differ by as much as 1 part in 10 $^{5}$
D. differ by as much as 1 part in 10 $^{7}$
E. differ by as much as 1 part in 10 $^{3}$
F. differ by as much as 1 part in 10 $^{6}$
G. differ by as much as 2 parts in 10 $^{5}$
H. differ by as much as 1 part in 10 $^{4}$
I. differ by as much as 3 parts in 10 $^{6}$
J. differ by as much as 1 part in 10 $^{2}$
Answer: F
A sample of blood plasma occupies 0.550 dm$^{3}$ at 0°C and 1.03 bar, and is compressed isothermally by 0.57 per cent by being subjected to a constant external pressure of 95.2 bar. Calculate $W$.

Options:
A. $$
+6. 0 2 \ k J
$$
B. $$
+8. 7 7 \ k J
$$
C. $$
-0. 7 5 \ k J
$$
D. $$
+0. 3 8 \ k J
$$
E. $$
+4. 1 8 \ k J
$$
F. $$
+1. 5 0 \ k J
$$
G. $$
+0. 9 1 \ k J
$$
H. $$
-2. 5 5 \ k J
$$
I. $$
-1. 3 0 \ k J
$$
J. $$
+2. 9 9 \ k J
$$
Answer: J
Estimate the difference between the standard enthalpy of formation of $\mathrm{C O_{2} ( g )}$ as currently defined (at 1 bar) and its value using the former definition (at 1 atm).

Options:
A. $$
-1.1kJ\ mol
$$
B. $$
-1.5kJ\ mol
$$
C. $$
-0.8kJ\ mol
$$
D. $$
3.6kJ\ mol
$$
E. $$
2.3kJ\ mol
$$
F. $$
0.5kJ\ mol
$$
G. $$
0.7kJ\ mol
$$
H. $$
1.1kJ\ mol
$$
I. $$
-2.0kJ\ mol
$$
J. $$
-3.0kJ\ mol
$$
Answer: A
Estimate the standard internal energy of formation of liquid methyl acetate is()(methyl ethanoate, $CH_{\mathrm{3}}COOCH_{\mathrm{3}}$) at 298 K from its standard enthalpy of formation, which is -442 kJ mol$^{-1}$.

Options:
A. $$
{-4 8 0 k J \ {m o l}^{-1}}
$$
B. $$
{-4 3 0 k J \ {m o l}^{-1}}
$$
C. $$
{-4 2 0 k J \ {m o l}^{-1}}
$$
D. $$
{-4 6 0 k J \ {m o l}^{-1}}
$$
E. $$
{-4 3 5 k J \ {m o l}^{-1}}
$$
F. $$
{-4 3 2 k J \ {m o l}^{-1}}
$$
G. $$
{-4 4 0 k J \ {m o l}^{-1}}
$$
H. $$
{-4 5 0 k J \ {m o l}^{-1}}
$$
I. $$
{-4 0 0 k J \ {m o l}^{-1}}
$$
J. $$
{-4 1 5 k J \ {m o l}^{-1}}
$$
Answer: F
Carbon dioxide, which is recognized as the major con- tributor to global warming as a "greenhouse gas", is formed when fossil fuels are combusted, as in electrical power plants fueled by coal, oil, or natural gas. One potential way to reduce the amount of $\mathrm{C O_{2}}$ added to the atmosphere is to store it as a compressed gas in un- derground formations. Consider a 1000-megawatt coal- fired power plant that produces about $6 \times1 0^{6}$ tons of $\mathrm{C O_{2}}$ per year. If it is stored under- ground as a gas at 36 °C and 90 atm, what volume does it occupy?

Options:
A. $$
2.5 \times1 0^{1 0} \, \mathrm{L}
$$
B. $$
6 \times1 0^{1 0} \, \mathrm{L}
$$
C. $$
4 \times1 0^{1 0} \, \mathrm{L}
$$
D. $$
7 \times1 0^{1 0} \, \mathrm{L}
$$
E. $$
1 \times1 0^{1 0} \, \mathrm{L}
$$
F. $$
9 \times1 0^{1 0} \, \mathrm{L}
$$
G. $$
3 \times1 0^{1 0} \, \mathrm{L}
$$
H. $$
5 \times1 0^{1 0} \, \mathrm{L}
$$
I. $$
2 \times1 0^{1 0} \, \mathrm{L}
$$
J. $$
8 \times1 0^{1 0} \, \mathrm{L}
$$
Answer: G
Let $x_{k} = x_{0} + k h, k = 0, 1, 2, 3$. What is $$\operatorname*{max}_{x_{0} \leqslant x \leqslant x_{3}} | l_{2} ( x )$$?

Options:
A. $$
\approx0. 7 6 3 9
$$
B. $$
\approx1. 0 3 4 8
$$
C. $$
\approx1. 0 5 6 3
$$
D. $$
\approx1. 0 1 4 6
$$
E. $$
\approx0. 9 8 5 4
$$
F. $$
\approx1. 0 6 6 0
$$
G. $$
\approx1. 0 7 2 1
$$
H. $$
\approx1. 1 4 9 2
$$
I. $$
\approx1. 1 2 5 7
$$
J. $$
\approx0. 8 9 7 2
$$
Answer: C
Let
$$
X=\langle x_{1}, x_{2}, x_{3}, x_{4}, x_{5}, x_{6} \rangle, \quad Y=\langle a, b, c, d \rangle,
$$
$$
f ( x )=\left\{\begin{matrix} {{{a,}}} & {{{x \in\{x_{1}, x_{2}, x_{3} \}}}} \\ {{{b,}}} & {{{x \in\{x_{4}, x_{5} \},}}} \\ {{{c,}}} & {{{x=x_{6},}}} \\ \end{matrix} \right.
$$
$$
\underset{\sim}A=\frac{1} {x_{1}}+\frac{0. 5} {x_{2}}+\frac{0. 8} {x_{3}}+\frac{0. 4} {x_{5}}+\frac{0. 7} {x_{6}} \,,
$$
What are the values of $\underset{\sim}B=f(\underset{\sim}A)$ and $f^{-1}(\underset{\sim}B)$?

Options:
A. $$\underset{\sim}B=f(\underset{\sim}A) =\frac{0. 8} {c}+\frac{1} {b}+\frac{0. 5} {a}$$
$$f^{-1}(\underset{\sim}B)=\frac{1} {x_{1}}+\frac{0. 5} {x_{4}}+\frac{0. 7} {x_{5}}+\frac{0. 8} {x_{6}}+\frac{0. 3} {x_{3}}$$
B. $$\underset{\sim}B=f(\underset{\sim}A) =\frac{0. 5} {a}+\frac{0. 8} {b}+\frac{1} {c}$$
$$f^{-1}(\underset{\sim}B)=\frac{1} {x_{2}}+\frac{1} {x_{5}}+\frac{0. 7} {x_{4}}+\frac{0. 3} {x_{6}}+\frac{0. 5} {x_{1}}$$
C. $$\underset{\sim}B=f(\underset{\sim}A) =\frac{0. 4} {b}+\frac{0. 8} {a}+\frac{1} {c}$$
$$f^{-1}(\underset{\sim}B)=\frac{1} {x_{1}}+\frac{0. 5} {x_{2}}+\frac{0. 4} {x_{3}}+\frac{0. 9} {x_{5}}+\frac{1} {x_{6}}$$
D. $$\underset{\sim}B=f(\underset{\sim}A) =\frac{0. 4} {c}+\frac{0. 8} {a}+\frac{1} {b}$$
$$f^{-1}(\underset{\sim}B)=\frac{0. 6} {x_{1}}+\frac{1} {x_{3}}+\frac{0. 5} {x_{2}}+\frac{0. 4} {x_{4}}+\frac{0. 7} {x_{6}}$$
E. $$\underset{\sim}B=f(\underset{\sim}A) =\frac{1} {c}+\frac{0. 8} {b}+\frac{0. 5} {a}$$
$$f^{-1}(\underset{\sim}B)=\frac{1} {x_{3}}+\frac{0. 9} {x_{1}}+\frac{0. 4} {x_{4}}+\frac{0. 6} {x_{5}}+\frac{1} {x_{6}}$$
F. $$\underset{\sim}B=f(\underset{\sim}A) =\frac{1} {c}+\frac{0. 4} {a}+\frac{0. 5} {b}$$
$$f^{-1}(\underset{\sim}B)=\frac{1} {x_{3}}+\frac{0. 9} {x_{5}}+\frac{0. 4} {x_{6}}+\frac{1} {x_{2}}+\frac{0. 8} {x_{1}}$$
G. $$\underset{\sim}B=f(\underset{\sim}A) =\frac{0. 7} {b}+\frac{0. 5} {c}+\frac{1} {a}$$
$$f^{-1}(\underset{\sim}B)=\frac{0. 4} {x_{2}}+\frac{0. 9} {x_{5}}+\frac{1} {x_{4}}+\frac{1} {x_{6}}+\frac{0. 8} {x_{3}}$$
H. $$\underset{\sim}B=f(\underset{\sim}A) =\frac{1} {a}+\frac{0. 4} {b}+\frac{0. 7} {c}$$
$$f^{-1}(\underset{\sim}B)=\frac{1} {x_{1}}+\frac{1} {x_{2}}+\frac{1} {x_{3}}+\frac{0. 4} {x_{4}}+\frac{0. 4} {x_{5}}+\frac{0. 7} {x_{6}}$$
I. $$\underset{\sim}B=f(\underset{\sim}A) =\frac{1} {b}+\frac{0. 5} {a}+\frac{0. 8} {c}$$
$$f^{-1}(\underset{\sim}B)=\frac{1} {x_{2}}+\frac{0. 3} {x_{1}}+\frac{0. 4} {x_{5}}+\frac{0. 7} {x_{3}}+\frac{0. 6} {x_{6}}$$
J. $$\underset{\sim}B=f(\underset{\sim}A) =\frac{1} {b}+\frac{0. 7} {c}+\frac{0. 5} {a}$$
$$f^{-1}(\underset{\sim}B)=\frac{1} {x_{2}}+\frac{0. 8} {x_{3}}+\frac{1} {x_{4}}+\frac{0. 4} {x_{5}}+\frac{0. 6} {x_{6}}$$
Answer: H
Which of the following is not an ethical value of reproductive technology?

Options:
A. Reproductive technology can ensure gender selection for societal balance.
B. Reproductive technology can sometimes replace the need for natural reproduction.
C. Reproductive technology can help maintain population balance
D. Reproductive technology can enhance genetic diversity in human populations.
E. Reproductive technology can help reduce genetic diseases.
F. Reproductive technology can breed specific types of people that humans need and serve humanity.
G. Reproductive technology can treat and compensate for infertility and is beneficial to marriage and family
H. Reproductive technology can facilitate family planning
I. Reproductive technology may change traditional parenting roles.
J. Reproductive technology can be used for eugenics
Answer: F
General Manager: I advocate that both Wang and Jin should be promoted at least one person. Chairman of the Board of Understanding: I disagree. Which of the following, most accurately expresses the chairman's opinion?

Options:
A. Only one of them should be promoted.
B. Promotions should be limited to external candidates.
C. Both must be promoted.
D. At most one of the two should be promoted.
E. Promotion should be based on seniority alone.
F. If Wang is promoted, then Jin will not be promoted.
G. Both should be demoted.
H. Only Jin should be promoted.
I. Neither of them should be promoted.
J. Only Wang should be promoted.
Answer: I
In the goods inspection clause of international sales contracts, the most commonly used stipulations regarding the time and place of inspection are ( ).

Options:
A. Inspection during transit
B. Inspection in the exporting country, re-inspection in the importing country
C. Inspection in the exporting country
D. Inspection in the importing country
E. Inspection in a third country
F. Pre-shipment inspection by an independent agency
G. Inspection upon arrival at the buyer's warehouse
H. Inspection at the port of export only
I. Random inspection at various points of transit
J. Post-delivery inspection by the buyer
Answer: B
For goods with lower value and lighter outer packaging, the commonly used gravimetric method is ( ).

Options:
A. Net weight
B. Legal weight
C. Tare weight
D. Adjusted weight
E. Gross weight
F. Conditioned weight
G. Packed weight
H. Total weight
Answer: E
Assume that the independent random variables X and Y follow the same type of probability distribution (though their distribution parameters may not be the same). Furthermore, X + Y also follows the same type of probability distribution. Then X and Y cannot follow the ( ).

Options:
A. Beta Distribution
B. Exponential Distribution
C. Binomial Distribution
D. Geometric Distribution
E. Pareto Distribution
F. Bernoulli Distribution
G. Uniform Distribution
H. Gamma Distribution
I. Poisson Distribution
Answer: B
Which professor led students to conduct a survey on the living conditions of residents in Haidian District, Beijing and Tsinghua school workers?

Options:
A. Professor Liu Ming
B. Professor Zhang Wei
C. Professor Zhao Hui
D. Professor Chen Da
E. Professor Li Jun
F. Professor Ma Ying
G. Professor Sun Yan
H. Professor Gao Feng
I. Professor Wang Li
J. Professor Xu Lei
Answer: D
In educational practice, what is the principle of training children to learn to rely on their own experience and ability to take the initiative in activities?

Options:
A. Collaboration principle
B. Principle of activity
C. The principle of comprehensiveness
D. The principle of encouragement
E. Heuristic principle
F. The principle of engagement
G. Support principle
H. The principle of motivation
I. The principle of independence
Answer: I
What are the characteristics of children's thinking in large class age?

Options:
A. Enhanced memory strategies
B. Concrete imagery
C. The germination of abstract logical thinking
D. Abstract logical thinking
E. Advanced problem-solving abilities
F. Reliance on symbolic play
G. Intuitive mobility
H. Increased ability for metacognition
Answer: C
Adults inadvertently say some unrealistic words in front of children, so that children learn to lie in the latent shift of silence, what is the name of this kind of lying behavior of children?

Options:
A. Pretend deception
B. Lying that doesn't distinguish fact from imagination
C. Exaggerated truth
D. Make-believe falsehood
E. Fantasy lying
F. Creative storytelling
G. Bragging lies
H. Cover up lying
I. Lying by imitation
J. Fanciful dishonesty
Answer: I
how long can children over the age of 2 participate in group activities?

Options:
A. 10 to 15 minutes
B. 6 to 8 minutes
C. 5 to 10 minutes
D. 1 to 2 minutes
E. 2 to 4 minutes
F. 8 to 12 minutes
G. 12 to 20 minutes
H. 3 to 5 minutes
I. 4 to 6 minutes
J. 15 to 20 minutes
Answer: C
What is the development direction of kindergartens and nurseries in recent years?

Options:
A. Privatization
B. Segmentation
C. Integration
D. Standardization
E. Digitalization
F. Decentralization
G. Homogenization
H. Grading
I. Expansion
J. Specialization
Answer: C
What section do gear toys and puzzles belong to?

Options:
A. Block area
B. Outdoor play area
C. Reading nook
D. Science area
E. Woodworking area
F. Construction zone
G. Dramatic play area
H. Art area
I. Sensory play area
J. Operation area
Answer: J
Tao Xingzhi, a modern educational thinker in China, believes that early childhood education should liberate children's ().

Options:
A. Activities
B. Creativity
C. Initiative
D. Potential
E. Enthusiasm
F. Playfulness
G. Imagination
H. Interest
I. Freedom
J. Curiosity
Answer: B