datavorous/entrance-exam-dataset huggingface dataset:
In which of the following processes, fused sodium hydroxide is electrolysed at a $330^{\circ} \mathrm{C}$ temperature for extraction of sodium

Options:
A Castner's process
B Down's process
C Cyanide process
D Both (b) and (c)

The correct answer is:
Castner's process

Solution:
Castner's process used to obtain $\mathrm{Na}$, by electrolysis of sodium hydroxide.

Topic: Chemistry, s Block Elements, JEE Main
In which of the following processes, the bond order increases and paramagnetic character changes to diamagnetic one?

Options:
A O2→O2+
B O2→O22-
C NO→NO+
D N2→N2+

The correct answer is:
NO→NO+

Solution:
Process	Change in magnetic nature	Bonad order change

N2→N2+	Dia → Para	3→2.5

NO→NO+	Para →Dia	2.5→3

O2→O2-2	Para→ Dia	2→1

O2→O2+	Para → Para	2→2.5

Topic: Chemistry, Chemical Bonding and Molecular Structure, JEE Main, JEE Main 2023 (13 Apr Shift 1)
In which of the following reaction CO2 (carbon dioxide) is not released?

Options:
A
B
C
D

The correct answer is:

Solution:
Here this compound succinic acid undergoes dehydration to give succinic anhydride while rest other undergo decarboxylation.

Topic: Chemistry, Carboxylic Acid Derivatives, JEE Main
In which of the following reaction hydrogen peroxide is a reducing agent

Options:
A $2 \mathrm{FeCl}_2+2 \mathrm{HCl}+\mathrm{H}_2 \mathrm{O}_2 \rightarrow 2 \mathrm{FeCl}_3+2 \mathrm{H}_2 \mathrm{O}$
B $\mathrm{Cl}_2+\mathrm{H}_2 \mathrm{O}_2 \rightarrow 2 \mathrm{HCl}+\mathrm{O}_2$
C $2 \mathrm{HI}+\mathrm{H}_2 \mathrm{O}_2 \rightarrow 2 \mathrm{H}_2 \mathrm{O}+\mathrm{I}_2$
D $\mathrm{H}_2 \mathrm{SO}_3+\mathrm{H}_2 \mathrm{O}_2 \rightarrow \mathrm{H}_2 \mathrm{SO}_4+\mathrm{H}_2 \mathrm{O}$

The correct answer is:
$\mathrm{Cl}_2+\mathrm{H}_2 \mathrm{O}_2 \rightarrow 2 \mathrm{HCl}+\mathrm{O}_2$

Solution:
$\underset{0}{\mathrm{Cl}_2}+\mathrm{H}_2 \mathrm{O}_2 \rightarrow \underset{-1}{2 \mathrm{HCl}}+\mathrm{O}_2$
In this reaction $\mathrm{H}_2 \mathrm{O}_2$ works as reducing agent

Topic: Chemistry, Hydrogen, JEE Main
In which of the following reaction the final product is neither an acid nor an acid salt,

Options:
A \( \mathrm{Ph}-\mathrm{CHO} \stackrel{\text { Tollen 's reagent }}{\longrightarrow} \)
B \( \mathrm{CH}_{3}-\mathrm{CH}_{2}-\mathrm{OH} \stackrel{\mathrm{KMnO}_{4} / \mathrm{OH}^{-}}{\longrightarrow} \)
C \( \mathrm{Ph}-\mathrm{CHO} \stackrel{\text { Fehling solution }}{\longrightarrow} \)
D \( \mathrm{Ph}-\mathrm{CH}_{2}-\mathrm{OH} \stackrel{\mathrm{K}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7} / \mathrm{H}^{+}}{\longrightarrow} \)

The correct answer is:
\( \mathrm{Ph}-\mathrm{CHO} \stackrel{\text { Fehling solution }}{\longrightarrow} \)

Solution:
1. Ph-CHO⟶ Tollen's reagent PhCOO-

2. CH3-CH2-OH→KMnO4/OH-CH3COOH

3. PhCHO→Fehling solutionNo reaction

4. It is an oxidation reaction.

PhCH2OH→K2Cr2O7/H+PhCOOH

Topic: Chemistry, Carboxylic Acid Derivatives, JEE Main
In which of the following reactions, alcohol is formed as product gives positive iodoform test?

Options:
A
B CH 3 − CH 2 −CH=O → I CH 3 MgBr excess II H 2 O/H +
C
D

The correct answer is:
CH 3 − CH 2 −CH=O → I CH 3 MgBr excess II H 2 O/H +

Solution:

Topic: Chemistry, Aldehydes and Ketones, JEE Main
In which of the following reactions, an increase in the volume of the container will favour the formation of products?

Options:
A 4NH3 g+ 5O2 g⇌ 4NOg+ 6H2O(l)
B 2NO2 (g) ⇌ 2NO(g) + O2(g)
C 3O2Â (g)Â Â âÂ 2O3(g)
D H2Â (g)Â +Â I2Â (g)Â âÂ 2HI(g)

The correct answer is:
2NO2 (g) ⇌ 2NO(g) + O2(g)

Solution:
Volume↑ P↓ reaction proceed in the direction where number of gaseous moles increase.
2NO2 g⇌ 2NOg+ O2 g ∆ng=2+1-2=1

Topic: Chemistry, Chemical Equilibrium, JEE Main, JEE Main 2018 (15 Apr)
In which of the following reactions, an increase in the volume of the container will favour the formation of products?

Options:
A
$4 \mathrm{NH}_3(\mathrm{g})+5 \mathrm{O}_2(\mathrm{g}) \rightleftharpoons 4 \mathrm{NO}$ (g) $+6 \mathrm{H}_2 \mathrm{O}(\mathrm{l})$

B
$2 \mathrm{NO}_2(\mathrm{g}) \rightleftharpoons 2 \mathrm{NO}(\mathrm{g})+\mathrm{O}_2$ (g)

C
$3 \mathrm{O}_2 \rightleftharpoons 2 \mathrm{O}_3(\mathrm{g})$

D
$\mathrm{H}_2(\mathrm{g})+\mathrm{I}_2(\mathrm{g}) \rightleftharpoons 2 \mathrm{HI}(\mathrm{g})$

The correct answer is:
$2 \mathrm{NO}_2(\mathrm{g}) \rightleftharpoons 2 \mathrm{NO}(\mathrm{g})+\mathrm{O}_2$ (g)

Solution:
Volume $\uparrow P \downarrow$, reaction proceeds in which direction where the number of moles of gases increases.
$2 \mathrm{NO}_2(\mathrm{~g}) \rightleftharpoons 2 \mathrm{NO}(\mathrm{g})+\mathrm{O}_2(\mathrm{~g})$
$\Delta \mathrm{n}_{\mathrm{g}}=(2+1)-2=1$

Topic: Chemistry, Chemical Equilibrium, JEE Main, JEE Main 2018 (15 Apr Shift 1 Online)
In which of the following reactions H2O2 acts as a reducing agent ?
(a) H 2 O 2 + 2 H + + 2 e - → 2 H 2 O
(b) H 2 O 2 - 2 e - → O 2 + 2 H +
(c) H 2 O 2 + 2 e - → 2 OH -
(d) H 2 O 2 + 2 OH - - 2 e - → O 2 + 2 H 2 O

Options:
A (a) , (b)
B (c) , (d)
C (a) , (c)
D (b) , (d)

The correct answer is:
(b) , (d)

Solution:
Reducing agent undergoes oxidation and in oxidation half reaction there will be loss of electrons.
(b) H 2 O 2 â O 2 + 2 H + + 2 e - (loss)
(d) H 2 O 2 + OH - â 2 H 2 O + O 2 + 2 e - (loss)

Topic: Chemistry, Hydrogen, JEE Main, JEE Main 2014 (06 Apr)
In which of the following reactions, $\mathrm{H}_{2} \mathrm{O}_{2}$ is acting as a reducing agent?

Options:
A $\mathrm{H}_{2} \mathrm{O}_{2}+\mathrm{SO}_{2} \rightarrow \mathrm{H}_{2} \mathrm{SO}_{4}$
B $2 \mathrm{KI}+\mathrm{H}_{2} \mathrm{O}_{2} \rightarrow 2 \mathrm{KOH}+\mathrm{I}_{2}$
C $\quad \mathrm{PbS}+4 \mathrm{H}_{2} \mathrm{O}_{2} \rightarrow \mathrm{PbSO}_{4}+4 \mathrm{H}_{2} \mathrm{O}$
D $\mathrm{Ag}_{2} \mathrm{O}+\mathrm{H}_{2} \mathrm{O}_{2} \rightarrow 2 \mathrm{Ag}+\mathrm{H}_{2} \mathrm{O}+\mathrm{O}_{2}$

The correct answer is:
$\mathrm{Ag}_{2} \mathrm{O}+\mathrm{H}_{2} \mathrm{O}_{2} \rightarrow 2 \mathrm{Ag}+\mathrm{H}_{2} \mathrm{O}+\mathrm{O}_{2}$

Solution:
$\mathrm{SO}_{2}$ changes to $\mathrm{H}_{2} \mathrm{SO}_{4}$ (O.N. changes from +4 to +6 oxidation $)$ $2 \mathrm{KI} \rightarrow \mathrm{I}_{2}(\mathrm{O} . \mathrm{S} .$ changes from -1 to 0
oxidation) $\mathrm{PbS} \rightarrow \mathrm{PbSO}_{4}(\mathrm{O} . \mathrm{S}$. changes from -2 to +6
oxidation) $\mathrm{Ag}_{2} \mathrm{O} \rightarrow 2 \mathrm{Ag}(\mathrm{O} . \mathrm{S} .$ changes from +1 to 0
reduction)

Topic: Chemistry, Redox Reactions, JEE Main
In which of the following reactions, hydrogen peroxide acts as an oxidizing agent?

Options:
A HOCl+H2O2→H3O++Cl-+O2
B I2+H2O2+2OH-→2I-+2H2O+O2
C PbS+4H2O2→PbSO4+4H2O
D 2MnO4-+3H2O2→2MnO2+3O2+2H2O+2OH-

The correct answer is:
PbS+4H2O2→PbSO4+4H2O

Solution:
The reaction in which H2O2 is getting reduced, it will behave as oxidising agent.

2e-+2H++H2O2⟶2H2O (reduction)
S-2+4H2O⟶SO4-2+8H++8e-(oxidation)
Equation. 1×4+Equation.2
Final reaction PbS+4H2O2⟶PbSO4+4H2O

Topic: Chemistry, Hydrogen, JEE Main, JEE Main 2017 (08 Apr Online)
In which of the following reactions, increase in the volume at constant temperature does not affect the number of moles at equilibrium

Options:
A
$2 \mathrm{NH}_3 \rightarrow \mathrm{N}_2+3 \mathrm{H}_2$

B
$\mathrm{C}(\mathrm{g})+(1 / 2) \mathrm{O}_2(\mathrm{~g}) \rightarrow \mathrm{CO}(\mathrm{g})$

C
$\mathrm{H}_2(\mathrm{~g})+\mathrm{O}_2(\mathrm{~g}) \rightarrow \mathrm{H}_2 \mathrm{O}_2(\mathrm{~g})$

D
none of these

The correct answer is:
none of these

Solution:
No Solution Available

Topic: Chemistry, Chemical Equilibrium, JEE Main, JEE Main 2002
In which of the following reactions, standard entropy change $\left(\Delta \mathrm{S}^{\circ}\right)$ is positive and standard Gibb's energy change $\left(\Delta \mathrm{G}^{\circ}\right)$ decreases sharply with increasing temperature?

Options:
A $\mathrm{C}$ (graphite) $+\frac{1}{2} \mathrm{O}_{2}(\mathrm{~g}) \rightarrow \mathrm{CO}(\mathrm{g})$
B $\mathrm{CO}(\mathrm{g})+\frac{1}{2} \mathrm{O}_{2}(\mathrm{~g}) \rightarrow \mathrm{CO}_{2}(\mathrm{~g})$
C $\mathrm{Mg}(\mathrm{s})+\frac{1}{2} \mathrm{O}_{2}(\mathrm{~g}) \rightarrow \mathrm{MgO}(\mathrm{s})$
D $\frac{1}{2} \mathrm{C}$ (graphite) $+\frac{1}{2} \mathrm{O}_{2}(\mathrm{~g}) \rightarrow \frac{1}{2} \mathrm{CO}_{2}(\mathrm{~g})$

The correct answer is:
$\mathrm{C}$ (graphite) $+\frac{1}{2} \mathrm{O}_{2}(\mathrm{~g}) \rightarrow \mathrm{CO}(\mathrm{g})$

Solution:
Since, in the first reaction gaseous products are forming from solid carbon hence entropy will increase i.e. $\Delta \mathrm{S}=+\mathrm{ve}$.
$\mathrm{C}(\mathrm{gr} .)+\frac{1}{2} \mathrm{O}_{2}(\mathrm{~g}) \rightarrow \mathrm{CO}(\mathrm{g}) ; \Delta \mathrm{S}^{\circ}=+\mathrm{ve}$
Since, $\Delta \overrightarrow{\mathrm{G}^{\circ}}=\Delta \mathrm{H}^{\circ}-\mathrm{T} \Delta \mathrm{S}$ hence the value of
$\Delta$ G decrease on increasing temperature.

Topic: Chemistry, Thermodynamics (C), JEE Main
In which of the following reactions the hydrogen peroxide acts as a reducing agent?

Options:
A PbS+4H2O2→PbSO4+4H2O
B 2Fe2++H2O2→2Fe3++2OH-
C HOCl+H2O2→H3O++Cl-1+O2
D Mn2++H2O2→Mn4++2OH-

The correct answer is:
HOCl+H2O2→H3O++Cl-1+O2

Solution:
PbS+4H2O2→PbSO4+4H2O

In the above reaction lead sulphide oxidised to lead sulphate. Hence, hydrogen peroxide acts as oxidising agent.

2Fe2++H2O2→2Fe3++2OH-

In the above reaction Fe2+ oxidised to Fe3+. Hence, hydrogen peroxide acts as oxidising agent.

Mn2++H2O2→Mn4++2OH-

In the above reaction Mn2+ oxidised to Mn4+. Hence, hydrogen peroxide acts as oxidising agent.

HOCl+H2O2→H3O++Cl-1+O2

In the above reaction Cl+1 reduced to Cl-, hence, hydrogen peroxide acts as a reducing agent.

Topic: Chemistry, Hydrogen, JEE Main, JEE Main 2023 (24 Jan Shift 2)
In which of the following reactions, the product(s) given is/are not correct?

Options:
A 3 Cu + 8  HNO 3 dil →3 Cu NO 3 2 + 2 NO + 4  H 2 O
B 3 Zn + 8  HNO 3 very dil  →3 Zn NO 3 2  + 2 NO + 4  H 2 O
C 4 Sn + 10  HNO 3 dil →4 Sn NO 3 2   + NH 4 NO 3 + 3  H 2 O
D As + 3  HNO 3 dil → H 3 AsO 3 + 3  NO 2

The correct answer is:
3 Zn + 8  HNO 3 very dil  →3 Zn NO 3 2  + 2 NO + 4  H 2 O

Solution:
With very dilute HNO3, Zn produces NH4NO3

Topic: Chemistry, p Block Elements (Group 15, 16, 17 & 18), JEE Main
In which of the following, R.Q will always be less than one?

Options:
A Potato
B Rice
C Groundnut
D More than one option is correct

The correct answer is:
Groundnut

Solution:
The ratio of the volume of CO2 evolved to the volume of O2 consumed in respiration is called the respiratory quotient (RQ). When fats are used in respiration, the RQ is less than 1 . For oxidation of groundnut, fats are oxidized thus value of RQ is less than 1. In rice and potato the main respiratory substrate is carbohydrates, for which, the RQ value is one.

Topic: Biology, Respiration in Plants, NEET
In which of the following salt hydrolysis takes place

Options:
A $\mathrm{KCl}$
B $\mathrm{NaNO}_3$
C $\mathrm{CH}_3 \mathrm{COOK}$
D $\mathrm{K}_2 \mathrm{SO}_4$

The correct answer is:
$\mathrm{CH}_3 \mathrm{COOK}$

Solution:
Because it is a strong base.

Topic: Chemistry, Ionic Equilibrium, JEE Main
In which of the following sets, all the given species are isostructural ?

Options:
A
$\mathrm{CO}_2, \mathrm{NO}_2, \mathrm{ClO}_2, \mathrm{SiO}_2$

B
$\mathrm{PCl}_3, \mathrm{Al} \mathrm{Cl}_3, \mathrm{BCl}_3, \mathrm{SbCl}_3$

C
$\mathrm{BF}_3, \mathrm{NF}_3, \mathrm{PF}_3, \mathrm{AlF}_3$

D
$\mathrm{BF}_4^{-}, \mathrm{CCl}_4, \mathrm{NH}_4^{+}, \mathrm{PCl}_4^{+}$

The correct answer is:
$\mathrm{BF}_4^{-}, \mathrm{CCl}_4, \mathrm{NH}_4^{+}, \mathrm{PCl}_4^{+}$

Solution:
All have tetrahedral structure.

Topic: Chemistry, Chemical Bonding and Molecular Structure, JEE Main, JEE Main 2013 (25 Apr Online)
In which of the following sets of families, the pollen grains are viable for months?

Options:
A Rosaceae, Liliaceae and Poaceae
B Leguminosae, Solanaceae and Rosaceae
C Solanaceae, Poaceae and Liliaceae
D Brassicaceae, Liliaceae and Poaceae

The correct answer is:
Leguminosae, Solanaceae and Rosaceae

Solution:
In some members of Rosaceae, Solanaceae, Leguminosae pollen maintain viability for months. In some cereals like rice and wheat belonging to Poaceae family to pollen loose viability within 30 minutes of their release.

Topic: Biology, Sexual Reproduction in Flowering Plants, NEET, NEET 2023 (Manipur)
In which of the following species, each atom carries same number of lone pair of electrons on it?

Options:
A XeO 4 2 -
B XeF 2
C XeO 6 4 -
D O 3

The correct answer is:
XeF 2

Solution:
(a) (sp3d)
(b) (sp3d) All atoms carry 3 lone pair each.
(c) (sp3d2)
(d) (Lewis structure)

Topic: Chemistry, Chemical Bonding and Molecular Structure, JEE Main
In which of the following species is the underlined carbon having $\mathrm{sp}^3$ hybridisation?

Options:
A

B

C

D

The correct answer is:

Solution:
In molecules (a), (c) and (d), the carbon atom has a multiple bond, only (b) has $\mathrm{sp}^3$ hybridisation

Topic: Chemistry, General Organic Chemistry, JEE Main, JEE Main 2002
In which of the following species maximum atom can lie in same plane?

Options:
A XeF2O2
B PCl5
C AsH4+
D XeF4

The correct answer is:
XeF4

Solution:
can lie in a plane

Topic: Chemistry, Chemical Bonding and Molecular Structure, JEE Main
In which of the following species the central C-atom is negatively charged

Options:
A Carbanion
B Carbonium ion
C Carbocation
D Free radical

The correct answer is:
Carbanion

Solution:
\(\begin{array}{llcl} & \text {Species } & \text {Valence electrons } & \text {Magnetic behaviour } \\ \text {1. } & \text {Free radical } & 7 & \text {Paramagnetic } \\ \text {2. } & \text{Carbonium ion } & 6 & \text {Diamagnetic } \\ \text {3. } & \text{Carbanion } & 8 & \text {Diamagnetic } \\ \text {4. } & \text{Carbene } & 6 & \text {Diamagnetic } \\ \text {5. } & \text {Nitrene } & 6 & \text {Diamagnetic } \end{array}\)

Topic: Chemistry, General Organic Chemistry, JEE Main
In which of the following techniques, the embryos are transferred to assist those females who cannot conceive?

Options:
A GIFT and ZIFT
B ICSI and ZIFT
C GIFT and ICSI
D ZIFT and IUT

The correct answer is:
ZIFT and IUT

Solution:
ZYGOTE INTRA-FALLOPIAN TRANSFER (ZIFT): It is also one of the assisted methods of conception. The procedure for ZIFT is similar to IVF-ET. In this method, after In-vitro fertilization, the zygote is transferred into the fallopian tube. After the transfer of the zygote early stages of development, implantation, and maintenance of pregnancy take place in the normal method.

INTRAUTERINE TRANSFER (IUT): In this technique, after in-vitro fertilization, the zygote is allowed to develop into an embryo (more than eight blastomeres). The embryo is transformed directly into the uterus for implantation and further development. Embryos formed by In-vivo fertilization could be used for such transfer to assist those females who fail to conceive.

Topic: Biology, Reproductive Health, NEET, NEET 2020 (Phase 1)
In which of the following the hydration energy is higher than the lattice energy?

Options:
A $\mathrm{MgSO}_4$
B $\mathrm{RaSO}_4$
C $\mathrm{SrSO}_4$
D $\mathrm{BaSO}_4$

The correct answer is:
$\mathrm{MgSO}_4$

Solution:
The solubility of sulphates of alkaline earth metals decreases with group from $\mathrm{Be}$ to $\mathrm{Ba}$ due to the ionic size increases down the group.
$\mathrm{BeSO}_4 > \mathrm{MgSO}_4 > \mathrm{CaSO}_4 > \mathrm{SrSO}_4 > \mathrm{BaSO}_4$
Related Theory
The greater the lattice enthalpy, the stronger the forces between ions. Those forces are only completely broken when the ions are present as gaseous ions, scattered so far apart that there is negligible attraction between them.
I Caution
$\rightarrow$ The lattice energy remains constant because sulphate ion is so large, so that small change in cationic sizes do not make any difference.

Topic: Chemistry, s Block Elements, NEET, NEET 2007
In which of the following the inert pair effect is most prominent

Options:
A $C$
B $\mathrm{Si}$
C $\mathrm{Ge}$
D $P b$

The correct answer is:
$P b$

Solution:
The inert pair effect is most prominent in $P b$ because from top to bottom due to increase in number of shells.

Topic: Chemistry, p Block Elements (Group 13 & 14), JEE Main
In which of the processes, does the internal energy of the system remain constant?

Options:
A Adiabatic
B Isochoric
C Isobaric
D Isothermal

The correct answer is:
Isothermal

Solution:
In isothermal process, the internal energy of the system remains constant. Heat supplied in an isothermal change is used to do work against external surrounding or if the work is done on the system then equal amount of heat energy will be liberated by the system.

Topic: Physics, Thermodynamics, KCET, KCET 2008
In which of the processes, does the internal energy of the system remain constant?

Options:
A Adiabatic
B Isochoric
C Isobaric
D Isothermal

The correct answer is:
Isothermal

Solution:
In isothermal process, temperature remains constant, hence internal energy of the system remains constant in isothermal process.

Topic: Physics, Thermodynamics, COMEDK, COMEDK 2018
In which one of the following cases will the liquid flow in a pipe be most streamlined

Options:
A Liquid of high viscosity and high density flowing through a pipe of small radius
B Liquid of high viscosity and low density flowing through a pipe of small radius
C Liquid of low viscosity and low density flowing through a pipe of large radius
D Liquid of low viscosity and high density flowing through a pipe of large radius

The correct answer is:
Liquid of high viscosity and low density flowing through a pipe of small radius

Solution:
For streamline flow, Reynold's number $N_R \propto \frac{r \rho}{\eta}$ should be less. For less value of $N_R$, radius and density should be small and viscosity should be high.

Topic: Physics, Mechanical Properties of Fluids, JEE Main
In which one of the following enzymes, is copper necessarily associated as an activator?

Options:
A carbonic anhydrase
B tryptophanase
C lactic dehydrogenase
D tyrosinase.

The correct answer is:
tyrosinase.

Solution:
The structure of tyrosinase can be divided into three domains: the central domain, the N-terminal domain, and the $\mathrm{C}$-terminal domain. The central domain, which is composed of six conserved histidine residues, contains the $\mathrm{CuA}$ and $\mathrm{CuB}$ oxidizing ions.
Related Theory
Tyrosinase is involved in the biosynthesis of melanin in the melanosomes causing pigmentation of skin, hair and eyes in mammals providing the protection against UV. It converts a protein building block (amino acid) called tyrosine to another compound called dopaquinone.

Topic: Biology, Biomolecules (B), NEET, NEET 2004
In which one of the following equilibria, Kp≠Kc?

Options:
A 2HIg⇌H2g+I2g
B 2Cs+O2g⇌2COg
C 2NOg⇌N2g+O2g
D NO2g+SO2g⇌NOg+SO3g

The correct answer is:
2Cs+O2g⇌2COg

Solution:
kp=kcRTΔng
(i) 2HIg⇌H2g+I2g
Δng=1+1-2=0
So kp=kc
(ii) 2NOg⇌N2g+O2g
Δng=2-2=0
So kp=kc
(iii) NO2g+SO2g⇌NOg+SO3g
Δng=2-2=0
So kp=kc
(iv) 2s+O2g⇌2COg
Δng=2-1=1
kp=kcRTΔn⇒kp=kcRT
kp>kc

Topic: Chemistry, Chemical Equilibrium, JEE Main, JEE Main 2019 (12 Apr Shift 2)
In which one of the following male and female gametophytes do not have free living independent existence?

Options:
A Cedrus
B Pteris
C Funaria
D Polytrichum

The correct answer is:
Cedrus

Solution:
Cedrus is gymnosperm having reduced dependent gametophytes as pollen and endosperm.

Topic: Biology, Plant Kingdom, NEET, NEET 2008 (Mains)
In which one of the following molecules strongest back donation of an electron pair from halide to boron is expected?

Options:
A BI3
B BBr3
C BCl3
D BF3

The correct answer is:
BF3

Solution:
Due to small size atom show strongest back bonding in BF3.
In case of BF3 (2P-2P back bonding) while in BCl3(2P-3P),BBr3(2P-4P) and BI3(2P-5P) back bonding. So extent of back bonding is maximum in 2P-2P

Topic: Chemistry, p Block Elements (Group 13 & 14), JEE Main, JEE Main 2021 (27 Aug Shift 1)
In which one of the following organism, its excretory organs are correctly stated?

Options:
A Humans - Kidneys, sebaceous glands and tear glands
B Earthworm - Pharyngeal, integumentary and septal nephridia
C Cockroach - Malpighian tubules and enteric caeca
D Frog - Kidneys, skin and buccal epithelium

The correct answer is:
Earthworm - Pharyngeal, integumentary and septal nephridia

Solution:
In earthworm, excretory system is made up of many segmentally arranged microscopic coiled tubes called nephridia. These are ectodermal in origin and analogous to vertebrate kidney.
In Pheretima, following three types of nephridia are seen.
(i) Pharyngeal nephridia-Situated in either side of pharynx and oesophagus in $4^{\text {th }}, 5^{\text {th }}$ and $6^{\text {th }}$ segment.
(ii) Integumentary nephridia-Scattered in the body wall, seen from $7^{\text {th }}$ segment onwards.
(iii) Septal nephridia-Largest nephridia attached to both faces of each intersegment septum behind $15^{\text {th }}$ segment.

Topic: Biology, Excretory Products and their Elimination, NEET, NEET 2010 (Mains)
In which one of the following pairs of experimental observations and phenomenon does the experimental observation correctly account for phenomenon
$Experimental observation$ $\quad$ $Phenomenon$

Options:
A $X$-ray spectra $\quad$ $\quad$ $\quad$ $\quad$ $\quad$ Charge on the nucleus
B $\alpha$ _particle scattering $\quad$ $\quad$ $\quad$ Quantized electron orbit
C Emission spectra $\quad$ $\quad$ $\quad$ $\quad$ The quantization of energy
D The photoelectric effect$\quad$ $\quad$ $\quad$ The nuclear atom

The correct answer is:
Emission spectra $\quad$ $\quad$ $\quad$ $\quad$ The quantization of energy

Solution:
Emission spectra of different $\lambda$ accounts for quantisation of energy.

Topic: Chemistry, Structure of Atom, JEE Main
In which one of the following pairs the central atoms exhibit \(\mathrm{sp}^2\) hybridization ?

Options:
A \(\mathrm{H}_2 \mathrm{O}\) and \(\mathrm{NO}_2\)
B \(\mathrm{BF}_3 \text { and } \mathrm{NO}_2^{-}\)
C \(\mathrm{NH}_2^{-}\) and \(\mathrm{H}_2 \mathrm{O}\)
D \(\mathrm{NH}_2^{-}\) and \(\mathrm{BF}_3\)

The correct answer is:
\(\mathrm{BF}_3 \text { and } \mathrm{NO}_2^{-}\)

Solution:
$\begin{aligned} & \mathrm{BF}_3 \rightarrow \mathrm{sp}^2 \\ & \mathrm{NO}_2{ }^{-} \mathrm{sp}^2 \\ & \mathrm{H}_2 \mathrm{O} \rightarrow \mathrm{sp}^3 \\ & \mathrm{NO}_2 \rightarrow \mathrm{sp}^2 \\ & \mathrm{NH}_2{ }^{-} \rightarrow \mathrm{sp}^3\end{aligned}$

Topic: Chemistry, Chemical Bonding and Molecular Structure, JEE Main, JEE Main 2024 (09 Apr Shift 1)
In which one of the following pollination is autogamous?

Options:
A Xenogamy
B Chasmogamy
C Cleistogamy
D Geitonogamy

The correct answer is:
Cleistogamy

Solution:
Bisexual flowers which remain always closed are called cleistogamous and such condition of flowers is called cleistogay. In such flowers, the anthers and stigma lie close to each other. When anthers dehisces in the flowers buds, pollen grains come in contact with stigma to effect pollination. Thus, cleistogamous flowers are invariably autogamous.

Topic: Biology, Sexual Reproduction in Flowering Plants, NEET, NEET 2011 (Screening)
In which one of the following sets all species show disproportionation reaction?

Options:
A ClO4-,MnO4-,ClO2-and F2
B MnO42-,ClO2-,Cl2 and Mn3+
C Cr2O72-,MnO4-,ClO2- and Cl2
D ClO2-,F2,MnO4- and Cr2O72-

The correct answer is:
MnO42-,ClO2-,Cl2 and Mn3+

Solution:
Disproportionation reactions are a special type of redox reactions. One of the reactants in a disproportionation reaction always contains an element that can exist in at least three oxidation states. The element of reacting species is in intermediate oxidation state and simultaneously gets oxidised and reduced. MnO42-,ClO2-,Cl2 and Mn3+ are having intermediate oxidation states.

Note: No option is correct in the actual question. One option is modified for its correctness.

Topic: Chemistry, Redox Reactions, JEE Main, JEE Main 2021 (31 Aug Shift 2)