Skip to main content
Back to Equilibrium

Your Progress

0 / 146 Answered
0
Correct
0
Incorrect
0%
Accuracy
NEET • CHEMISTRY • Equilibrium

Equilibrium practice · Medium

Try a question, then open “View answer” to check it. Sign in to submit answers and save progress.

Practice format and chapter quiz

The practice player uses single-correct-answer MCQs. Chapter quizzes help you review a topic; they are not full-length NEET mock papers.

Take a chapter quiz →
Showing 1-30 of 146 questions
1 Medium
1 of 146
Remembering +4 | -1
At the state of dynamic equilibrium, for solute ++ solvent ⇋\leftrightharpoons solution.
View answer and explanation
Correct option: B
Rate of dissolution = Rate of unsaturation
Option A (Rate of dissolution = Rate of crystallization) is incorrect. The correct answer is Rate of dissolution = Rate of unsaturation. At dynamic equilibrium, the rate at which the solute dissolves equals the rate at which it crystallizes out of the solution.
2 Medium
2 of 146
Application +4 | -1
For PCl5⇋PCl3+Cl2\mathrm{PC}{\mathrm{l}_5}\leftrightharpoons\mathrm{PC}{\mathrm{l}_3} + \mathrm{C}{\mathrm{l}_2}, initial concentration of each reactant and product is 1 M. If Keq=0.41{K_{\mathrm{eq}}} = 0.41 then
View answer and explanation
Correct option: C
More PCl5\mathrm{PC}{\mathrm{l}_5} will form
Option C (More PCl5 will form) is correct because the reaction quotient Q is greater than Keq, indicating the reaction will shift to the left to form more PCl5.
3 Medium
3 of 146
Understanding +4 | -1
Select the pKa\mathrm{p}{K_a} value of the strongest acid from the following
View answer and explanation
Correct option: A
1.01.0
Option A (1.01.0) is the correct answer because a lower pKa\mathrm{p}{K_a} value indicates a stronger acid.
4 Medium
4 of 146
Application +4 | -1
The pKb\mathrm{p}{K_b} value of NH3\mathrm{N}{\mathrm{H}_3} is 5. Calculate the pH of the buffer solution, 1  L\mathrm{1}\;L of which contains 0.01M  0.01\mathrm{ }M\;\mathrm{ } NH4Cl and 0.10 M NH4OH\mathrm{N}{\mathrm{H}_4}\mathrm{Cl}\,\mathrm{ and}\,0.10\,\mathrm{M }\,\mathrm{N}{\mathrm{H}_4}\mathrm{OH}
View answer and explanation
Correct option: D
10
Option D (10) is correct because it is calculated using the Henderson-Hasselbalch equation for a basic buffer.
5 Medium
5 of 146
Application +4 | -1
The vapour density of N2O4{\mathrm{N}_2}{\mathrm{O}_4} at a certain temperature is 30. What is the percentage dissociation of N2O4{\mathrm{N}_2}{\mathrm{O}_4} at this temperature?
View answer and explanation
Correct option: C
53.3%53.3\%
Option C (53.3%53.3\%) is correct because it is calculated using the relationship between vapour density, molecular weight, and degree of dissociation.
6 Medium
6 of 146
Analyzing +4 | -1
The equilibrium constant KK for the reaction 2HI(g)⇋H2(g)+I2(g)2\mathrm{HI}\left( \mathrm{g} \right)\leftrightharpoons{\mathrm{H}_2}\left( \mathrm{g} \right) + {\mathrm{I}_2}\left( \mathrm{g} \right) at room temperature 300  K300\;\mathrm{K} is 2.85\mathrm{2}\mathrm{.85} and at 698  K   1.84×10−2.698\;\mathrm{K}\,\;1.84 \times {10^{ - 2}}. Hence the reason that HI\mathrm{HI} exists as a stable compound at room temperature is because:
View answer and explanation
Correct option: C
The heat of reaction at room temperature is −5.31  kcal- 5.31\;\mathrm{kcal}
Option A is correct because the slow decomposition rate of HI at room temperature prevents the attainment of equilibrium, making it appear stable.
7 Medium
7 of 146
Remembering +4 | -1
Nucleophiles are:
View answer and explanation
Correct option: B
Lewis bases
Option B (Lewis bases) is correct because nucleophiles are electron-rich species that donate electron pairs, which is the definition of a Lewis base.
8 Medium
8 of 146
Analyzing +4 | -1
The pHpH values of 0.1  M0.1\;M solution of HCl,CH3COOH,NH4Cl  and  CH3COONa\mathrm{HCl},\mathrm{C}{\mathrm{H}_3}\mathrm{COOH},\mathrm{N}{\mathrm{H}_4}\mathrm{Cl}\;\mathrm{ and }\;\mathrm{C}{\mathrm{H}_3}\mathrm{COONa} will have the order
View answer and explanation
Correct option: A
HCl<CH3COOH<NH4Cl<CH3COONa\mathrm{HCl} < C{\mathrm{H}_3}\mathrm{COOH} < N{\mathrm{H}_4}\mathrm{Cl} < C{\mathrm{H}_3}\mathrm{COONa}
Option A (HCl<CH3COOH<NH4Cl<CH3COONa\mathrm{HCl} < C{\mathrm{H}_3}\mathrm{COOH} < N{\mathrm{H}_4}\mathrm{Cl} < C{\mathrm{H}_3}\mathrm{COONa}) is correct because it correctly orders the pH values from most acidic (lowest pH) to most basic (highest pH).
9 Medium
9 of 146
Application +4 | -1
For the reaction,

2NO3(g)⇋2NO(g)+O2(g)2\mathrm{N}{\mathrm{O}_3}\left( \mathrm{g} \right)\leftrightharpoons2\mathrm{NO}\left( \mathrm{g} \right) + {\mathrm{O}_2}\left( \mathrm{g} \right)

(Kc=1.8×10−6  at184∘C)\left( {{K_c} = 1.8 \times {{10}^{ - 6}}\;\mathrm{at }184^\circ C} \right)

(R=0.00831  kJ/(molK)(R = 0.00831\;kJ/\left( {mol\mathrm{ }K} \right)

When Kp  and  Kc{K_p}\;\mathrm{and}\;{K_c} are compared at 184∘C184^\circ C, it is found that
View answer and explanation
Correct option: D
Kp{K_p} is greater than Kc{K_c}
Option D (Kp{K_p} is greater than Kc{K_c}) is correct because for this reaction, the change in the number of moles of gas is positive, leading to Kp>Kc{K_p} > {K_c}.
10 Medium
10 of 146
Understanding +4 | -1
The vapour density of completely dissociated NH4Cl\mathrm{N}{\mathrm{H}_4}\mathrm{Cl} would be:
View answer and explanation
Correct option: B
Half of that of ammonium chloride
Option B is correct because upon complete dissociation, one mole of NH4Cl yields two moles of products, halving the vapor density.
11 Medium
11 of 146
Analyzing +4 | -1
Consider the following salts, which one(s) when dissolved in water will produce a basic solution?
I.   RbClO4II.   NaNO2III.   NH4ClIV.   NaCl\begin{array}{cccccccccccccccccccc} {{\text{I}}{\text{.}}\,\,\,RbCl{O_4}}&{{\text{II}}{\text{.}}\,\,\,NaN{O_2}}&{{\text{III}}{\text{.}}\,\,\,N{H_4}Cl}&{{\text{IV}}{\text{.}}\,\,\,NaCl} \end{array}
View answer and explanation
Correct option: B
Only II
Option B (Only II) is correct because NaNO2NaN{O_2} is a salt of a weak acid (HNO2HN{O_2}) and a strong base (NaOH), which hydrolyzes in water to produce a basic solution.
12 Medium
12 of 146
Understanding +4 | -1
The interfering radicals interfere in the test of usual inorganic analysis after II group analysis due to:
View answer and explanation
Correct option: C
Their insoluble nature in alkaline medium
Option C (Their insoluble nature in alkaline medium) is correct because interfering radicals precipitate in alkaline medium, hindering the analysis of subsequent groups.
13 Medium
13 of 146
Understanding +4 | -1
The phenomenon of interaction of anions and cations furnished by a electrolyte with the H+{\mathrm{H}^ + } and OH−\mathrm{O}{\mathrm{H}^ - } ions of water to produce acidic nature or alkalinity is known as hydrolysis. In hydrolysis:
View answer and explanation
Correct option: D
All of the above
Option D (All of the above) is correct because all the given statements accurately describe the phenomenon of hydrolysis.
14 Medium
14 of 146
Understanding +4 | -1
When hydrogen molecules decomposed into it’s atoms which conditions gives maximum yield of H atom?
View answer and explanation
Correct option: A
High temperature and low pressure
Option A (High temperature and low pressure) is correct because the decomposition of hydrogen molecules into atoms is an endothermic process, and increasing the temperature and decreasing the pressure will favor the formation of H atoms.
15 Medium
15 of 146
Application +4 | -1
Buffer capacity of a buffer solution is x, the volume of 1M added to 100 ml of this solution if the change of PH{P^H} by 1 is
View answer and explanation
Correct option: C
100x ml100x\,ml
Option C (100x ml) is correct because buffer capacity is defined as the moles of acid or base needed to change the pH by 1, and this relates directly to the volume of 1M acid added.
16 Medium
16 of 146
Remembering +4 | -1
The principal buffer present in human blood
View answer and explanation
Correct option: D
H2CO3+HCO3−\mathrm{H}_2 \mathrm{CO}_3+\mathrm{HCO}_3^{-}
Option D (H2CO3+HCO3−\mathrm{H}_2 \mathrm{CO}_3+\mathrm{HCO}_3^{-}) is correct because the carbonic acid/bicarbonate buffer system is the primary buffer system in human blood, maintaining blood pH within a narrow range.
17 Medium
17 of 146
Application +4 | -1
Degree of dissociation of NH4OH\mathrm{N}{\mathrm{H}_4}\mathrm{OH} in water is 1.8×10−51.8 \times {10^{ - 5}}, then hydrolysis constant of NH4Cl\mathrm{N}{\mathrm{H}_4}\mathrm{Cl} is
View answer and explanation
Correct option: D
5.55×10−105.55 \times {10^{ - 10}}
Option D is correct because the hydrolysis constant of NH4Cl can be calculated using the formula Kh = Kw/Kb.
18 Medium
18 of 146
Application +4 | -1
Phosphorus pentachloride dissociates as follows, in a closed reaction vessel,,br>
PCl5(g)⇋PCl3(g)+Cl2(g)\mathrm{PC}{\mathrm{l}_5}\left( \mathrm{g} \right)\leftrightharpoons\mathrm{PC}{\mathrm{l}_3}\left( \mathrm{g} \right) + \mathrm{C}{\mathrm{l}_2}\left( \mathrm{g} \right)

If total pressure at equilibrium of the reaction mixture is pp and degree of dissociation of PCl5  is  x\mathrm{PC}{\mathrm{l}_5}\;\mathrm{is}\;x, the partial pressure of PCl3\mathrm{PC}{\mathrm{l}_3} will be
View answer and explanation
Correct option: A
(xx+1)p\left( {\frac{x}{{x + 1}}} \right)p
Option A ((xx+1)p\left( {\frac{x}{{x + 1}}} \right)p) is correct because it represents the partial pressure of PCl3 at equilibrium, derived from the degree of dissociation and total pressure.
19 Medium
19 of 146
Application +4 | -1
Kc{K_c} for the reaction : [Ag(CN)2]−⇋Ag++2CN−,{\left[ {\mathrm{Ag}{{\left( {\mathrm{CN}} \right)}_2}} \right]^ - }\leftrightharpoons\mathrm{A}{\mathrm{g}^ + } + 2\mathrm{C}{\mathrm{N}^ - }, the equilibrium constant at 25∘C  is  4.0×10−19,25^\circ C\mathrm{ }\;is\mathrm{ }\;4.0\mathrm{ } \times \mathrm{ }{10^{ - 19}}, then the silver ion concentration in a solution which was originally 0.1  molar  in  KCN\mathrm{0}\mathrm{.1}\;\mathrm{molar}\;\mathrm{in}\;\mathrm{KCN} and 0.03  molar  in  AgNO3\mathrm{0}\mathrm{.03}\;\mathrm{molar}\;\mathrm{in}\;\mathrm{AgN}{\mathrm{O}_3} is :
View answer and explanation
Correct option: B
7.5×10−187.5 \times {10^{ - 18}}
Option B (7.5×10−187.5 \times {10^{ - 18}}) is correct because it calculates the silver ion concentration by considering the formation of the complex ion and using the equilibrium constant.
20 Medium
20 of 146
Analyzing +4 | -1
The reactions, PCl5( g)⇌PCl3( g)+Cl2( g)\mathrm{PCl}_5(\mathrm{~g}) \rightleftharpoons \mathrm{PCl}_3(\mathrm{~g})+\mathrm{Cl}_2(\mathrm{~g}) and COCl2( g)=CO(g)+Cl2( g)\mathrm{COCl}_2(\mathrm{~g})=\mathrm{CO}(\mathrm{g})+\mathrm{Cl}_2(\mathrm{~g}) are simultaneously in equilibrium in an equilibrium box at constant volume. A few moles of CO(g)\mathrm{CO}(\mathrm{g}) are later introduced into the vessel. After some time, the new equilibrium concentration of
View answer and explanation
Correct option: C
PCl5\mathrm{PCl}_5 will become less
Option C (PCl5 will become less) is correct because adding CO shifts the second equilibrium to the left, reducing Cl2, which then shifts the first equilibrium to the left, increasing PCl5 consumption and thus decreasing its concentration.
21 Medium
21 of 146
Analyzing +4 | -1
The reaction that proceeds in the forward direction is :
View answer and explanation
Correct option: B
NH4Cl+NaOH→H2O+NH3+NaCl\mathrm{N}{\mathrm{H}_4}\mathrm{Cl} + \mathrm{NaOH} \to {\mathrm{H}_2}\mathrm{O} + \mathrm{N}{\mathrm{H}_3} + \mathrm{NaCl}
Option B (NH4Cl+NaOH→H2O+NH3+NaCl\mathrm{N}{\mathrm{H}_4}\mathrm{Cl} + \mathrm{NaOH} \to {\mathrm{H}_2}\mathrm{O} + \mathrm{N}{\mathrm{H}_3} + \mathrm{NaCl}) is correct because it represents a strong base reacting with a weak acid salt to form a weaker base and a salt, which is a favorable reaction.
22 Medium
22 of 146
Analyzing +4 | -1
From separate solutions of four sodium salts NaW,NaX,NaY  and  NaZ\mathrm{Na}W,\mathrm{Na}X,\mathrm{Na}Y\;and\;\mathrm{Na}Z had pH    7.0,9.0,10.0  and  11.0\mathrm{pH}\;\;7.0,9.0,10.0\;and\;11.0 respectively. When each solution was 0.1  M0.1\;M, the strongest acid is:
View answer and explanation
Correct option: A
HWHW
Option A (HWHW) is correct because the sodium salt with the lowest pH (pH 7.0) corresponds to the strongest acid.
23 Medium
23 of 146
Application +4 | -1
The pHpH of a 10−9{10^{ - 9}} M solution of HCl\mathrm{HCl} in water is
View answer and explanation
Correct option: D
Between 6 and 7
Option D (Between 6 and 7) is correct because the pH of a very dilute acid solution cannot be greater than 7.
24 Medium
24 of 146
Understanding +4 | -1
In an equilibrium reaction H2(g)+I2(g)2HI(g);ΔH=−3000{H_2}(g) + {I_2}(g)2HI(g);\Delta H = - 3000 cal. Which factor favours dissociation of HI
View answer and explanation
Correct option: C
High Temperature
Option C (High Temperature) is correct because the reverse reaction (dissociation of HI) is endothermic, and increasing the temperature favors the endothermic reaction.
25 Medium
25 of 146
Analyzing +4 | -1
An aqueous solution of hydrogen sulphide shows the equilibrium,

H2S⇋H++HS−{\mathrm{H}_2}\mathrm{S}\leftrightharpoons{\mathrm{H}^ + } + \mathrm{H}{\mathrm{S}^ - }

If dilute hydrochloric acid is added to an aqueous solution of hydrogen sulphide without any change in temperature, then:
View answer and explanation
Correct option: D
The concentration of HS−\mathrm{H}{\mathrm{S}^ - } will decreases
Option D is correct because adding HCl increases the concentration of H+, which shifts the equilibrium to the left, decreasing the concentration of HS- according to Le Chatelier's principle.
26 Medium
26 of 146
Analyzing +4 | -1
The correct order of increasing [H3O+]\left[ {{\mathrm{H}_3}{\mathrm{O}^ + }} \right] in the following aqueous solutions is:
View answer and explanation
Correct option: C
0.01  M  NaNO2<0.01  M  NaCl<0.01  M  H2S<0.01  M  H2SO40.01\;M\;\mathrm{NaN}{\mathrm{O}_2} < 0.01\;M\;\mathrm{NaCl} < 0.01\;M\;{\mathrm{H}_2}\mathrm{S} < 0.01\;M\;{\mathrm{H}_2}\mathrm{S}{\mathrm{O}_4}
Option C (0.01  M  NaNO2<0.01  M  NaCl<0.01  M  H2S<0.01  M  H2SO40.01\;M\;\mathrm{NaN}{\mathrm{O}_2} < 0.01\;M\;\mathrm{NaCl} < 0.01\;M\;{\mathrm{H}_2}\mathrm{S} < 0.01\;M\;{\mathrm{H}_2}\mathrm{S}{\mathrm{O}_4}) is correct because it correctly orders the solutions from least to greatest acidity based on their chemical properties.
27 Medium
27 of 146
Analyzing +4 | -1
Which of the following has highest pH?
View answer and explanation
Correct option: D
M4Ca(OH)2\frac{\mathrm{M}}{4}\mathrm{Ca}{\left( {\mathrm{OH}} \right)_2}
Option D (M4Ca(OH)2\frac{\mathrm{M}}{4}\mathrm{Ca}{\left( {\mathrm{OH}} \right)_2}) is correct because it provides the highest hydroxide ion concentration due to being a strong base and having two hydroxide ions per formula unit.
28 Medium
28 of 146
Understanding +4 | -1
For the reactions, A+B+Q  ⇋  C+DA + B + Q\;\leftrightharpoons\;C + D&nbsp; if the temperature is increased then concentration of the products will
View answer and explanation
Correct option: A
Increase
Option A is correct because increasing the temperature favors the endothermic reaction, which in this case, is the forward reaction, thus increasing the concentration of products.
29 Medium
29 of 146
Understanding +4 | -1
The equilibrium constant for the reaction,N2(g)+O2(g)⇋2NO(g){\mathrm{N}_2}\left( \mathrm{g} \right) + {\mathrm{O}_2}\left( \mathrm{g} \right)\leftrightharpoons2\mathrm{NO}\left( \mathrm{g} \right) is 4×10−44 \times {10^{ - 4}} at 2000 K. In presence of a catalyst the equilibrium is attained ten times faster. Therefore, the equilibrium constant, in present of the catalyst, at 2000 K is:
View answer and explanation
Correct option: B
4×10−44 \times {10^{ - 4}}
Option B (4×10−44 \times {10^{ - 4}}) is correct because a catalyst only affects the rate of reaction, not the equilibrium constant.
30 Medium
30 of 146
Analyzing +4 | -1
The equilibrium constant for N2(g)+O2(g)⇋2NO(g){N_2}(g) + {O_2}(g)\leftrightharpoons2NO\left( g \right) is K1{K_1} and that for NO(g)⇋12N2(g)+12O2(g)NO(g)\leftrightharpoons\frac{1}{2}{N_2}(g) + \frac{1}{2}{O_2}(g) is K2{K_2}, then K1{K_1} and K2{K_2} related as
View answer and explanation
Correct option: A
K1=(1K2)2{K_1} = {\left( {\frac{1}{{{K_2}}}} \right)^2}
The correct answer is A (K1=(1K2)2{K_1} = {(\frac{1}{{{K_2}}})^2}) because it correctly relates the equilibrium constants of the forward and reverse reactions.
Revision notes and key takeaways

Review Equilibrium in your textbook or class notes, then use this set to check your understanding.

Key Takeaways

  • ✓ This set contains 146 single-correct-answer MCQs on Equilibrium.
  • ✓ Try each question before opening its answer. Read the explanation where one is available.
  • ✓ Sign in to save submitted answers. Revisit incorrect answers alongside your textbook or class notes.
Showing 1-30 of 146 questions
0 /146
0✓ 0✗
0% Accuracy
Type at least 2 characters or jump directly:
🔓

Save your learning progress

Sign in with a free account to save your practice answers and quiz results, then return to them when you revise.