datavorous/entrance-exam-dataset huggingface dataset:
What is the current in the circuit shown below

Options:
A $O$ amp
B $10^{-2} a m p$
C $1 \mathrm{amp}$
D $0.10 \mathrm{amp}$

The correct answer is:
$O$ amp

Solution:
The potential of $P$-side is more negative that of $N$-side, hence diode is in reverse biasing. In reverse biasing it acts as open circuit, hence no current flows.

Topic: Physics, Semiconductors, JEE Main
What is the decreasing order of strength of the bases?

OH-, NH2-,H-Câ¡C- and CH3-CH2- ?

Options:
A CH3-CH2->NH2->H-C≡C->OH-
B H-C≡C->CH3-CH2->NH2->OH-
C OH->NH2->H-C≡C->CH3-CH2-
D NH2->H-C≡C->OH->CH3-CH2-

The correct answer is:
CH3-CH2->NH2->H-C≡C->OH-

Solution:
As the strength of conjugate base α 1/acidic strength
As acidic strength is
HOH>HC≡CH>NH3>CH3-CH3
So CH3–CH2->NH2->H–C≡C->OH-

Topic: Chemistry, General Organic Chemistry, JEE Main
What is the difference between apocarpous and syncarpous ovaries?

Options:
A In racemose inflorescence the main axis continues to grow while in cymose inflorescence the main axis terminates in a flower.
B In racemose inflorescence , a number of leaflets are present on the common axis while in cymose inflorescence , the leaflets are attached at a common point.
C When more than one carpel is present, it is an apocarpous ovary while in syncarpous ovary the carpels are fused.
D None of the above

The correct answer is:
When more than one carpel is present, it is an apocarpous ovary while in syncarpous ovary the carpels are fused.

Solution:
When more than one carpel is present, the ovaries may be free as in Lotus and rose and are called apocarpous. The ovaries are termed as syncarpous when carpels are fused, as in mustard and tomato.

Topic: Biology, Morphology of Flowering Plants, NEET
What is the difference between benign and malignant tumors?

Options:
A Benign tumors grow rapidly while malignant tumors cause little damage
B Benign tumors remain confined to their original location while malignant tumors invade and damage surrounding normal tissues
C Benign tumors are a mass of proliferating cells while malignant tumors compete for vital nutrients
D Benign tumors do not spread while malignant tumors do

The correct answer is:
Benign tumors remain confined to their original location while malignant tumors invade and damage surrounding normal tissues

Solution:
Benign tumors remain confined to their original location and do not spread to other parts of the body. They cause little damage. On the other hand, malignant tumors are a mass of proliferating cells that grow rapidly, invade and damage surrounding normal tissues, and spread to other parts of the body.

Topic: Biology, Human Health and Diseases, NEET
What is the difference between dominance and recessive?

Options:
A in the presence or absence of a recessive trait, a dominant factor expresses itself while a recessive trait expresses itself only in the absence of a dominant trait.
B Dominance is big plants while recessive is small plant
C Dominant characters are more than recessive characters
D cannot be defined

The correct answer is:
in the presence or absence of a recessive trait, a dominant factor expresses itself while a recessive trait expresses itself only in the absence of a dominant trait.

Solution:
The main difference between dominance and recessive is in the presence or absence of a recessive trait, a dominant factor expresses itself while a recessive trait expresses itself only in the absence of a dominant trait.

Topic: Biology, Principles of Inheritance and Variation, NEET
What is the difference between genetic engineering and bioprocess engineering?

Options:
A Genetic engineering involves altering the chemistry of genetic material while bioprocess engineering involves maintaining a sterile environment for microbe growth.
B Bioprocess engineering involves altering the chemistry of genetic material while genetic engineering involves maintaining a sterile environment for microbe growth.
C Both techniques involve altering the chemistry of genetic materia
D Both techniques involve maintaining a sterile environment for microbe growth

The correct answer is:
Genetic engineering involves altering the chemistry of genetic material while bioprocess engineering involves maintaining a sterile environment for microbe growth.

Solution:
The difference between genetic engineering and bioprocess engineering is that genetic engineering involves altering the chemistry of genetic material while bioprocess engineering involves maintaining a sterile environment for microbe growth.

Topic: Biology, Biotechnology - Principles and Processes, NEET
What is the difference between racemose and cymose inflorescence?

Options:
A In racemose inflorescence the main axis continues to grow while in cymose inflorescence the main axis terminates in a flower.
B In racemose inflorescence , a number of leaflets are present on the common axis while in cymose inflorescence , the leaflets are attached at a common point.
C In a racemose inflorescence , the lamina is entire while in cymose inflorescence the incisions of the lamina reach up to the midrib breaking it into a number of leaflets.
D None of the above

The correct answer is:
In racemose inflorescence the main axis continues to grow while in cymose inflorescence the main axis terminates in a flower.

Solution:
In racemose type of inflorescences the main axis continues to grow, the flowers are borne laterally in an acropetal succession. In cymose type of inflorescence the main axis terminates in a flower, hence is limited in growth.

Topic: Biology, Morphology of Flowering Plants, NEET
What is the dimensional formula of $a b^{-1}$ in the equation $\left(\mathrm{P}+\frac{\mathrm{a}}{\mathrm{V}^2}\right)(\mathrm{V}-\mathrm{b})=\mathrm{RT}$, where letters have their usual meaning.

Options:
A $\left[\mathrm{M}^{-1} \mathrm{~L}^5 \mathrm{~T}^3\right]$
B $\left[\mathrm{M}^6 \mathrm{~L}^7 \mathrm{~T}^4\right]$
C $\left[\mathrm{ML}^2 \mathrm{~T}^{-2}\right]$
D $\left[\mathrm{M}^0 \mathrm{~L}^3 \mathrm{~T}^{-2}\right]$

The correct answer is:
$\left[\mathrm{ML}^2 \mathrm{~T}^{-2}\right]$

Solution:
$\because[\mathrm{V}]=[\mathrm{b}]$
$\therefore$ Dimension of $b=\left[\mathrm{L}^3\right]$
$\begin{aligned}
& \&[\mathrm{P}]=\left[\frac{\mathrm{a}}{\mathrm{V}^2}\right] \\
& {[\mathrm{a}]=\left[\mathrm{PV}^2\right]=\left[\mathrm{ML}^{-1} \mathrm{~T}^{-2}\right]\left[\mathrm{L}^6\right]}
\end{aligned}$
Dimension of $\mathrm{a}=\left[\mathrm{ML}^5 \mathrm{~T}^{-2}\right]$
$\therefore \mathrm{ab}^{-1}=\frac{\left[\mathrm{ML}^5 \mathrm{~T}^{-2}\right]}{\left[\mathrm{L}^3\right]}=\left[\mathrm{ML}^2 \mathrm{~T}^{-2}\right]$

Topic: Physics, Units and Dimensions, JEE Main, JEE Main 2024 (05 Apr Shift 2)
What is the dimensional formula of co-efficient of viscosity?

Options:
A Dimensional formula: M 1 L - 1 T - 1
B Dimensional formula: M 2 L - 3 T - 1
C Dimensional formula: M - 4 L 1 T - 2
D Dimensional formula: M - 1 L 3 T - 2

The correct answer is:
Dimensional formula: M 1 L - 1 T - 1

Solution:
Coefficient of viscosity η=FxAv
F = tangential Force,
A = Area, x = distance between the layers,
v = velocity.
Dimensional Formula of Force =M1L1T-2
Dimensional Formula of Area =M0L2T0
Dimensional Formula of distance =M0L1T0
Dimensional Formula of velocity =M0L1T-1
Putting these values in above equation we get,
η=M1L1T-2M0L1T0M0L2T0M0L1T-1=M1L-1T-1

Topic: Physics, Units and Dimensions, JEE Main
What is the dimensional formula of magnetic field?

Options:
A Dimensional formula: \( \left[\mathrm{M}^{1} \mathrm{~L}^{0} \mathrm{~T}^{-2} \mathrm{I}^{-1}\right] \)
B Dimensional formula: \( \left[\mathrm{M}^{4} \mathrm{~L}^{0} \mathrm{~T}^{-6} \mathrm{I}^{-3}\right] \)
C Dimensional formula: \( \left[\mathrm{M}^{-2} \mathrm{~L}^{0} \mathrm{~T}^{3} \mathrm{I}^{-1}\right] \)
D Dimensional formula: \( \left[\mathrm{M}^{-6} \mathrm{~L}^{2} \mathrm{~T}^{1} \mathrm{I}^{-2}\right] \)

The correct answer is:
Dimensional formula: \( \left[\mathrm{M}^{1} \mathrm{~L}^{0} \mathrm{~T}^{-2} \mathrm{I}^{-1}\right] \)

Solution:
Units of magnetic field is Tesla has dimension of MT-2I-1 where M is mass, T is time, and I is electric current. â

Topic: Physics, Units and Dimensions, JEE Main
What is the disintegration constant of radon if the number of its atoms diminishes by 18% in 24 h? [Take ln0.82â-0.2]

Options:
A 2.3 Ã 10-3 s-1
B 2.3 Ã 10-4 s-1
C 2.3 Ã10-5 s-1
D 2.3 Ã10-6 s-1

The correct answer is:
2.3 Ã10-6 s-1

Solution:
Undisintegrated part
NN0=(100-18)%=82%
Using relation N=N0(e-Î»t)
82100= e-24 Ã60 Ã 60Î»
â´24 Ã 60 Ã 60 Ã Î»=log10082
or Î»=2.3 Ã 10-6 s-1

Topic: Physics, Nuclear Physics, JEE Main
What is the distance between the points which divide the line segment joining $(4,3)$ and $(5,7)$ internally and externally in the ratio $2: 3 ?$

Options:
A $\frac{12 \sqrt{17}}{5}$
B $\frac{13 \sqrt{17}}{5}$
C $\frac{\sqrt{17}}{5}$
D $\frac{6 \sqrt{17}}{5}$

The correct answer is:
$\frac{12 \sqrt{17}}{5}$

Solution:
Let $\mathrm{A}(\mathrm{x}, \mathrm{y})$ be the point that divides $(4,3)$ and $(5,7)$ internally is ratio $2: 3$
$\mathrm{A}=(\mathrm{x}, \mathrm{y})=\left(\frac{\mathrm{m} \mathrm{x}_{2}+\mathrm{nx}_{1}}{\mathrm{~m}+\mathrm{n}}, \frac{\mathrm{my}_{2}+\mathrm{ny}_{1}}{\mathrm{~m}+\mathrm{n}}\right)$
$=\left(\frac{10+12}{2+3}, \frac{14+9}{2+3}\right)=\left(\frac{22}{5}, \frac{23}{5}\right)$
Let $\mathrm{B}\left(\mathrm{x}^{\prime}, \mathrm{y}^{\prime}\right)$ be point that divides $(4,3)$ and $(5,7)$ externally in ratio $2: 3$
$\mathrm{B}=\left(\mathrm{x}^{\prime}, \mathrm{y}^{\prime}\right)=\left(\frac{\mathrm{m} \mathrm{x}_{2}-\mathrm{nx}_{1}}{\mathrm{~m}-\mathrm{n}}, \frac{\mathrm{m} \mathrm{y}_{2}-\mathrm{ny}_{1}}{\mathrm{~m}-\mathrm{n}}\right)$
$=\left(\frac{10-12}{2-3}, \frac{14-9}{2-3}\right)=(2,-5)$
Distance between $\mathrm{A}$ and $\mathrm{B}=\sqrt{\left(\mathrm{x}^{\prime}-\mathrm{x}\right)^{2}+\left(\mathrm{y}^{\prime}-\mathrm{y}\right)^{2}}$
$=\sqrt{\left(2-\frac{22}{5}\right)^{2}+\left(-5-\frac{23}{5}\right)^{2}}$
$=\sqrt{\frac{(-12)^{2}}{25}+\frac{(-48)^{2}}{25}}$
$=\frac{12}{5} \sqrt{1+4^{2}}=\frac{12}{5} \sqrt{17}$

Topic: Mathematics, Straight Lines, JEE Main
What is the domain of the function $\mathrm{f}(\mathrm{x})=\frac{1}{\sqrt{|\mathrm{x}|-\mathrm{x}}}$ ?

Options:
A $(-\infty, 0)$
B $(0, \infty)$
C $\quad 0 < x < 1$
D $x>1$

The correct answer is:
$(-\infty, 0)$

Solution:
We know that
$|x|=\left\{\begin{array}{cl}x, & x \geq 0 \\ -x, & x < 0\end{array}\right.$
For domain, $|x|-x>0$ Case $2: x < 0$ Case $1: x>0 \Rightarrow x-x=0$ (not possible)
$-x-x>0$
$\Rightarrow-2 x>0$
$\Rightarrow x < 0$
So, $x \in(-\infty, 0)$

Topic: Mathematics, Functions, NDA, NDA 2016 (Phase 2)
What is the dominant intermolecular force or bond that must be overcome in converting liquid $\mathrm{CH}_3 \mathrm{OH}$ to a gas ?

Options:
A Hydrogen bonding
B Dipole-dipole interaction
C Covalent bonds
D London dispersion force

The correct answer is:
Hydrogen bonding

Solution:
Key Idea When $\mathrm{H}$ atom is directly linked with $\mathrm{N}$ or $\mathrm{O}$, or $\mathrm{F}$, inter or interamolecular $\mathrm{H}$-bonding is formed.
In between $\mathrm{CH}_3 \mathrm{OH}$ molecules intermolecular H-bonding exist.
Hence, it is the intermolecular H-bonding that must be overcome in converting liquid $\mathrm{CH}_3 \mathrm{OH}$ to gas.

Topic: Chemistry, Chemical Bonding and Molecular Structure, JEE Main
What is the dominant intermolecular force or bond that must be overcome in converting liquid $\mathrm{CH}_3 \mathrm{OH}$ to a gas -

Options:
A London dispersion force
B Hydrogen bonding
C Dipole-dipole interaction
D Covalent bonds

The correct answer is:
Hydrogen bonding

Solution:
Inter molecular force in alcohol is mainly H-bonding

Topic: Chemistry, Chemical Bonding and Molecular Structure, NEET, NEET 2009 (Mains)
What is the EAN of nickel in $\mathrm{Ni}(\mathrm{CO})_4$

Options:
A 34
B 35
C 32
D 36

The correct answer is:
36

Solution:
EAN = At.No. - (Oxidation State \(+2 x\) Coordination Number)
Hence, EAN of $\mathrm{Ni}$ in $\mathrm{Ni}(\mathrm{CO})_4$ is
$=28-0+2 \times 4=36$

Topic: Chemistry, Coordination Compounds, JEE Main
What is the effect of adding a non-volatile solid to a solvent on the freezing point of the solvent, according to Raoult's law?

Options:
A The freezing point of the solvent increases.
B The freezing point of the solvent decreases.
C The freezing point of the solvent remains unchanged.
D The freezing point of the solvent depends on the nature of the solute.

The correct answer is:
The freezing point of the solvent decreases.

Solution:
According to Raoult's law, when a non-volatile solid is added to the solvent, its vapour pressure decreases, and as a result, the freezing point of the solvent decreases.

Topic: Chemistry, Solutions, NEET
What is the effect of an increase in the positive charge (Ze) on the nucleus on attractive interactions?

Options:
A Attractive interactions decrease
B Attractive interactions remain constant
C Attractive interactions fluctuate
D Attractive interactions increase

The correct answer is:
Attractive interactions increase

Solution:
The attractive interactions increase with an increase in the positive charge (Ze) on the nucleus.

Topic: Chemistry, Structure of Atom, NEET
What is the effect of denaturation on the structure of proteins?

Options:
A Denaturation causes proteins to fold into their natural, functional conformation.
B Denaturation has no effect on the structure of proteins.
C As a result of denaturation, globules get unfolded and helixes get uncoiled. Secondary and tertiary structures of protein are destroyed, but the primary structures remain unaltered
D Denaturation promotes the formation of more complex protein structures.

The correct answer is:
As a result of denaturation, globules get unfolded and helixes get uncoiled. Secondary and tertiary structures of protein are destroyed, but the primary structures remain unaltered

Solution:
Correct Option is : (C)
As a result of denaturation, globules get unfolded and helixes get uncoiled. Secondary and tertiary structures of protein are destroyed, but the primary structures remain unaltered

Topic: Chemistry, Biomolecules, NEET
What is the effect of denaturation on the structure of proteins?

Options:

None

Solution:
During denaturation, \(2^{\circ}\) and \(3^{\circ}\) structures of proteins are destroyed but \(1^{\circ}\) structure remains intact. As a result of denaturation, the globular proteins (soluble in \(\mathrm{H}_2 \mathrm{O}\) ) are converted into fibrous proteins (insoluble in \(\mathrm{H}_2 \mathrm{O}\) ) and their biological activity is lost. For example, boiled egg which contains coagulated proteins cannot be hatched.

Topic: Chemistry, Biomolecules
What is the effect of ethylene on dormancy of seeds and buds?

Options:
A Maintains dormancy
B Promotes dormancy
C Increases dormancy
D Breaks dormancy

The correct answer is:
Increases dormancy

Solution:
Ethylene breaks seed and bud dormancy and initiates germination in peanut seeds and sprouting of potato tubers.

Topic: Biology, Plant - Growth and Development, NEET
What is the effect of external pressure on the osmotic
pressure (OP) of a solution?

Options:
A OP decreases with increase of pressure
B OP decreases initially, then increases
C OP remained nearly same with increase/decrease of
external pressure
D OP increases with increase of pressure

The correct answer is:
OP remained nearly same with increase/decrease of
external pressure

Solution:
OP depends on the molarity of the solution.

Topic: Chemistry, Solutions, TS EAMCET, TS EAMCET 2022 (19 Jul Shift 1)
What is the effect of more electronegative atom on the strength of ionic bond

Options:
A Decreases
B Increases
C Decreases slowly
D Remains the same

The correct answer is:
Increases

Solution:
As soon as the electronegativity increases, ionic bond strength increases.

Topic: Chemistry, Chemical Bonding and Molecular Structure, JEE Main
What is the effect of pressure on the solubility of solids in liquids?

Options:
A Pressure significantly increases the solubility of solids in liquids.
B Pressure significantly decreases the solubility of solids in liquids.
C Pressure has no significant effect on the solubility of solids in liquids.
D Pressure increases solubility for endothermic processes and decreases it for exothermic processes.

The correct answer is:
Pressure has no significant effect on the solubility of solids in liquids.

Solution:
The paragraph mentions that pressure does not have any significant effect on the solubility of solids in liquids because solids and liquids are highly incompressible and remain unaffected by changes in pressure.

Topic: Chemistry, Solutions, NEET
What is the effect of pressure on the speed of sound in a medium, if pressure is doubled at constant temperature?

Options:
A Remains same
B Reduced to half
C Gets doubled
D Becomes 4 times

The correct answer is:
Remains same

Solution:
Speed of sound in a medium is independent of pressure if temperature is constant.

Topic: Physics, Waves and Sound, MHT CET, MHT CET 2021 (24 Sep Shift 1)
What is the effect on biodiversity as we move from equator to polar region?

Options:
A It increases
B First decreases than increase
C It decreases
D It remains unchanged

The correct answer is:
It decreases

Solution:
Species diversity decreases as we move away from the equator towards the poles. With very few exceptions, tropics harbour more species than temperate and polar areas.

Topic: Biology, Biodiversity and its Conservation, NEET
What is the effect on the catalytic activity from Group 5 to Group 11 metals for hydrogenation reactions?

Options:
A It decreases
B It remains constant
C It increases
D It fluctuates

The correct answer is:
It increases

Solution:
The paragraph notes that for hydrogenation reactions, the catalytic activity increases from Group 5 to Group 11 metals.

Topic: Chemistry, Surface Chemistry, NEET
What is the effect on the radius of an atom as it (a) gains an electron and (b) loses an electron?

Options:
A (a)increases and (b) decreases
B (a)decreases and (b) increases
C (a) remains the same and (b) does not change
D (a) decreases and (b) does not change

The correct answer is:
(a)increases and (b) decreases

Solution:
Correct Option is : (A)
(a)increases and (b) decreases

Topic: Chemistry, Classification of Elements and Periodicity in Properties, NEET
What is the end product of the process that converts garbage into electricity in India?

Options:
A Plastic
B Glass
C Manure
D Paper

The correct answer is:
Manure

Solution:
After removing ferrous metals, plastic, glass, and paper from garbage, the remaining product is used as manure, while biogas is used to produce electricity.

Topic: Chemistry, Environmental Chemistry, NEET
What is the energy change associated with the formation of a hydrogen molecule?

Options:
A Energy is absorbed.
B Energy is released.
C Energy remains constant.
D Cannot be determined.

The correct answer is:
Energy is released.

Solution:
The energy gets released when the bond is formed between two hydrogen atoms.

Topic: Chemistry, Chemical Bonding and Molecular Structure, NEET
What is the energy stored in the capacitor (in Î¼J ) between terminals 'a' and 'b' of the network (as shown in figure)?If capacitance of each capacitor is 1Î¼F.

Options:

The correct answer is:
12.50

Solution:
Redrawing network, we get a balanced Wheatstone's network.

Charge on capacitor between terminals a and b

Q2=CV2

Energy stored in that capacitor=12Q22C

=Q28C

=CV28

=1Ã10-6Ã1028J

=12.5Î¼J

Topic: Physics, Electrostatics, JEE Main
What is the equation of the circle which passes through the points $(3,-2)$ and $(-2,0)$ and having its centre on the line $2 x-y-3=0 ?$

Options:
A $x^{2}+y^{2}+3 x+2=0$
B $x^{2}+y^{2}+3 x+12 y+2=0$
C $x^{2}+y^{2}+2 x=0$
D $x^{2}+y^{2}=5$

The correct answer is:
$x^{2}+y^{2}+3 x+12 y+2=0$

Solution:
Given, centre of circle lies on line $2 x-y-3=0$ Let $x=h$ $2 h-y-3=0 \Rightarrow y=2 n-3$
$\therefore$ centre of circle $=(\mathrm{h}, 2 \mathrm{~h}-3)$
We know, OA $=$ OB $\Rightarrow(\mathrm{h}-3)^{2}+(2 \mathrm{~h}-3+2)^{2}=(\mathrm{h}+2)^{2}+(2 \mathrm{~h}-3)^{2}$
$\Rightarrow \mathrm{h}^{2}-6 \mathrm{~h}+9+(2 \mathrm{~h}-1)^{2}=\mathrm{h}^{2}+4 h+4+4 \mathrm{~h}^{2}-12 \mathrm{~h}+9$
$\Rightarrow y^{2}-6 h+9+4 h^{2}-4 h+1$
$=h^{2}+4 h+4+\not 4 h^{2}-12 h+9$
$\Rightarrow-10 h+10=-8 h+13$
$\Rightarrow-2 h=3 \Rightarrow h=\frac{-3}{2}$
$\therefore$ centre $=\left(\frac{-3}{2}, 2\left(\frac{-3}{2}\right)-3\right)=\left(\frac{-3}{2},-6\right)$
$\therefore$ radius $=(\mathrm{h}+2)^{2}+(2 \mathrm{~h}-3)^{2}$
$=\left(\frac{-3}{2}+2\right)^{2}+\left[2\left(\frac{-3}{2}\right)-3\right]^{2}=\frac{1}{4}+36$
$\therefore$ Equation of circle
$\Rightarrow\left(x+\frac{3}{2}\right)^{2}+(y+6)^{2}=\frac{1}{4}+36$
$\Rightarrow x^{2}+y^{2}+3 x+12 y+2=0$

Topic: Mathematics, Circle, JEE Main
What is the equation of the parabola, whose vertex and focus are on the $x$ -axis at distance a and b from the origin respectively? ( $\mathrm{b}>\mathrm{a}>0$ )

Options:
A $y^{2}=8(b-a)(x-a)$
B $y^{2}=4(b+a)(x-a)$
C $y^{2}=4(b-a)(x+a)$
D $y^{2}=4(b-a)(x-a)$

The correct answer is:
$y^{2}=4(b-a)(x-a)$

Solution:
The parabola's vertex and focus lie on $x$ -axis at points $(\mathrm{a}, 0)$ and $(\mathrm{b}, 0)$. Vertex and focus lie on the $\mathrm{x}$ -axis hence. the axis of parabola is $x$ -axis. Equation of parabola Vertex whose is a point $\left(x_{1}, y_{1}\right)$ then is $\left(y-y_{1}\right)^{2}=4 k\left(x-x_{1}\right)$
$\mathrm{So}, \mathrm{y}_{1}=0$ and $\mathrm{x}_{1}=\mathrm{a}$ and $\mathrm{k}=$ distance between focus and vertex $=(\mathrm{b}-\mathrm{a})$ so the equation is $(y-0)^{2}=4(b-a) \cdot(x-a)$
i.e., $y^{2}=4(b-a)(x-a)$

Topic: Mathematics, Parabola, JEE Main
What is the equilibrium expression for the reaction $\mathrm{P}_{4(\mathrm{~s})}+5 \mathrm{O}_{2(\mathrm{~g})} \rightleftharpoons \mathrm{P}_4 \mathrm{O}_{10(\mathrm{~s}}$ ?

Options:
A
$\left.\mathrm{Kc}=\left[\mathrm{P}_4 \mathrm{O}_{10}\right] / \mathrm{P}_4\right]\left[\mathrm{O}_2\right]^5$

B
$\mathrm{Kc}=1 /\left[\mathrm{O}_2\right]^5$

C
$\mathrm{Kc}=\left[\mathrm{O}_2\right]^5$

D
$\mathrm{Kc}=\left[\mathrm{P}_4 \mathrm{O}_{10}\right] / 5\left[\mathrm{P}_4\right]\left[\mathrm{O}_2\right]$

The correct answer is:
$\mathrm{Kc}=1 /\left[\mathrm{O}_2\right]^5$

Solution:
Applying law of mass action

Topic: Chemistry, Chemical Equilibrium, JEE Main, JEE Main 2004
What is the equilibrium expression for the reaction
P4s+5O2(g)⇌P4O10(s)?

Options:
A K c = P 4 O 10 P 4 O 5 5
B Kc=[P4O10]5P4[O2]
C Kc=O25
D Kc=1O25

The correct answer is:
Kc=1O25

Solution:
In the expression for equilibrium constant (Kp or Kc) species in solid state are not written (i.e., their molar concentrations are taken as 1)
P4s+5O2(g)âP4O10(s)
Thus, Kc=1O25

Topic: Chemistry, Chemical Equilibrium, JEE Main
What is the equivalent thermal conductivity (in W${{m}^{-1}}$ ${{K}^{-1}}$) of the compound bar made by soldering together an iron bar (L1 = 0.1 m, A1 = 0.02 m2, K1 = 79 W${{m}^{-1}}$ ${{K}^{-1}}$) and a brass bar (L2 = 0.1 m, A2 = 0.02 m2, K2 = 109 W ${{m}^{-1}}$ ${{K}^{-1}}$), with their free ends maintained at 373 K and 273 K respectively?

Options:
A 84.0 W ${{m}^{-1}}$ ${{K}^{-1}}$
B 88.3 W ${{m}^{-1}}$ ${{K}^{-1}}$
C 91.6 W ${{m}^{-1}}$ ${{K}^{-1}}$
D 95.9 W${{m}^{-1}}$ ${{K}^{-1}}$

The correct answer is:
91.6 W ${{m}^{-1}}$ ${{K}^{-1}}$

Solution:
Correct Option is : (C)
91.6 W ${{m}^{-1}}$ ${{K}^{-1}}$

Topic: Chemistry, Thermal Properties of Matter, NEET
What is the exact time interval between the throws of the two balls by the man, considering the following scenario? A man is standing on top of a building 100 m high. He throws two balls vertically, one at t = 0 and the other after a time interval (less than 2 seconds). The later ball is thrown at a velocity of half the first. The vertical gap between the first and second ball is +15 m at t = 2 s, and this gap remains constant.

Options:
A 0.5 s
B 1 s
C 1.5 s
D 2 s

The correct answer is:
1 s

Solution:
Correct Option is : (B)
1 s

Topic: Chemistry, Motion In One Dimension, NEET