129 + Interview Questions in Equilibrium in Chemistry – Class 11 Page 3 InterviewSolution

101.	Given that at 800k the concentrations are as follows: N2=3.0 × 10^–3M, O2 = 4.2 × 10^–3M and NO = 2.8 × 10^–3M, what is the equilibrium constant for the reaction N2(g) + O2(g) \(\rightleftharpoons \) 2NO(g)?(a) 0.622(b) 0.6(c) 0.63(d) 0.94I got this question during an internship interview.Asked question is from Law of Chemical Equilibrium and Equilibrium Constant in section Equilibrium of Chemistry – Class 11
Answer» The correct answer is (a) 0.622 For explanation: For the reaction, N2(g) + O2(g) \(\rightleftharpoons \) 2NO(g), the EQUILIBRIUM constant is given by [NO]^2/[N2][O2]. So the equilibrium constant K is given by (2.8 × 10^–3 M)(2.8 × 10^–3 M)/(3.0 × 10^–3 M)(4.2 × 10^–3 M) = 0.622, there are no units as Δng = 0.

Discussion

102.	for the reaction H2(g) + Br2(g) ↔ 2HBr(g) the equilibrium constant is given as 0.04 then what is the equilibrium constant for the reaction 2HBr(g) ↔ H2(g) + Br2(g)?(a) 0.04(b) 4(c) 25(d) 100The question was posed to me in homework.My question comes from Law of Chemical Equilibrium and Equilibrium Constant topic in chapter Equilibrium of Chemistry – Class 11
Answer» Right answer is (C) 25 The explanation: In a chemical REACTION if the equilibrium CONSTANT for a backward reaction is given by K then the equilibrium constant for the forward reaction is given by 1/k, so your the resultant answer becomes 1/0.04 = 25.

Discussion

103.	If we use activities in place of molar concentration in an equilibrium constant expression then what is the dimension of k?(a) it becomes dimensionless(b) the same units of molar concentration(c) units are related to the activity(d) cannot predict itThe question was posed to me during an online exam.This key question is from Law of Chemical Equilibrium and Equilibrium Constant topic in chapter Equilibrium of Chemistry – Class 11
Answer» The correct answer is (a) it BECOMES dimensionless Explanation: In equilibrium constant expression of a chemical reaction, (equilibrium constant is represented by the letter K) if the activities are USED in place of the molar CONCENTRATION K becomes dimensionless, that means it has no dimensions.

Discussion

104.	What is the equilibrium constant of the following reaction: 4NH3 + 5O2 → 4NO + 6H2O?(a) [NO][H2O]/[NH3][O2](b) [C]^c[D]^d/[A]^a[B]^b(c) [NO4[H2]^6/NH3]^4[O2]^5(d) [NO]^4[H2O]^6/[NH3]^4[O2]^5This question was posed to me in my homework.My question is from Law of Chemical Equilibrium and Equilibrium Constant topic in chapter Equilibrium of Chemistry – Class 11
Answer» Correct answer is (d) [NO]^4[H2O]^6/[NH3]^4[O2]^5 The explanation is: the above GIVEN chemical reaction 4NH3 + 5O2 → 4NO + 6H2O is in the form of aA + BB → cC + DD. We KNOW that the equilibrium constant of this reaction is [C]^c[D]^d/[A]^a[B]^b, show the required answer is [NO]^4[H2O]^6/[NH3]^4[O2]^5.

Discussion

105.	If the initial concentrations of reactants in a reaction increase then the equilibrium constant ____________(a) also increases(b) decreases(c) remains constant(d) may increase or decreaseI got this question during an interview.This intriguing question comes from Law of Chemical Equilibrium and Equilibrium Constant topic in portion Equilibrium of Chemistry – Class 11
Answer» The correct answer is (c) REMAINS constant Easy explanation: The equilibrium constant of a chemical REACTION is INDEPENDENT of the INITIAL concentrations of the reactants. So when the initial concentrations of the reactants INCREASE in a reaction the equilibrium constant remains the same.

Discussion

106.	The equilibrium constant of a reaction is 20 units and the equilibrium constant of other reaction is 30 units when both the reactions are added up together then the equilibrium constant of the resultant reaction is given by _____________(a) 20 units(b) 600 units(c) 50 units(d) 10 unitsThe question was asked during an online exam.I want to ask this question from Law of Chemical Equilibrium and Equilibrium Constant topic in chapter Equilibrium of Chemistry – Class 11
Answer» RIGHT answer is (b) 600 UNITS The explanation is: When the reaction can be EXPRESSED as the sum of two other reactions, the equilibrium CONSTANT of the overall reaction is equal to the product of equilibrium constants of individual reactions, so 20 units x 30 units = 600 units.

Discussion

107.	What does it indicate having a higher equilibrium constant?(a) reaction occurs faster(b) rate of backward reaction is faster(c) both the backward and forward reactions are equal(d) reaction may be slower than usualThis question was addressed to me during an interview.I'd like to ask this question from Law of Chemical Equilibrium and Equilibrium Constant in section Equilibrium of Chemistry – Class 11
Answer» Correct OPTION is (a) reaction occurs faster The EXPLANATION: As we know that the equilibrium constant is the ratio of the forward reaction RATE to the backward reaction rate. Having higher equilibrium constant depicts that the reaction that is forward occurring faster then the backward one and the EXTENSION of completion of the reaction is more.

Discussion

108.	The value of equilibrium constant for different chemical reactions at a particular temperature is ____________(a) constant(b) unique(c) the same(d) cannot sayThe question was asked in an international level competition.This question is from Law of Chemical Equilibrium and Equilibrium Constant topic in chapter Equilibrium of Chemistry – Class 11
Answer» Correct ANSWER is (b) unique Explanation: The value of the equilibrium constant changes with TEMPERATURE i.e. it’s DIFFERENT for different temperatures and is unique for EVERY reaction at a constant temperature or GIVEN temperature.

Discussion

109.	A reaction is given by aA + bB → cC + dD. How do you represent an equilibrium constant?(a) [A]^a[B]^b/[C]^c[D]^d(b) [C]^c[D]^d/[A]^a[B]^b(c) [A][B]/[C][D](d) [C][D]/[A][B]The question was asked by my school principal while I was bunking the class.I would like to ask this question from Law of Chemical Equilibrium and Equilibrium Constant topic in chapter Equilibrium of Chemistry – Class 11
Answer» CORRECT option is (b) [C]^c[D]^d/[A]^a[B]^b Explanation: An EQUILIBRIUM constant in a chemical reaction As given by the ratio of Forward reaction rate by backward reaction rate its UNITS are (mol/L)^Δng, where Δng is moles of products – moles of REACTANTS which are in the gaseous state only.

Discussion

110.	Equilibrium of a reaction depends on the concentration of reactants.(a) true(b) falseThe question was posed to me during an interview.My question is taken from Equilibrium in Chemical Processes topic in chapter Equilibrium of Chemistry – Class 11
Answer» Correct ANSWER is (b) false The EXPLANATION: In a chemical reaction equilibrium does not depend on the CONCENTRATION of REACTANTS as well as a concentration of products. Equilibrium is attained when the RATES of both forward and backward reactions are equal.

Discussion

111.	When a chemical reaction is written the products are written on the _____________(a) left side(b) right side(c) either left side or right side(d) depends on the chemicals presentI have been asked this question in unit test.I would like to ask this question from Equilibrium in Chemical Processes topic in chapter Equilibrium of Chemistry – Class 11
Answer» Correct answer is (b) right side To elaborate: When a chemical reaction is written, the REACTANTS are written on the LEFT side and the PRODUCTS are written on the right side, while both PARTS of the reaction are JOINED by an arrow mark (→).

Discussion

112.	At which of the following temperatures water is a dynamic equilibrium with ice?(a) 0 Kelvin(b) zero degree centigrade(c) zero degree Fahrenheit(d) 100 KelvinThis question was posed to me by my school teacher while I was bunking the class.The above asked question is from Equilibrium in Chemical Processes topic in portion Equilibrium of Chemistry – Class 11
Answer» The CORRECT option is (b) zero degree centigrade The best I can explain: WATER is a dynamic equilibrium with ice at the freezing point of water that is zero DEGREES centigrade, 273 Kelvin and 32-degree Fahrenheit. Because at zero degrees centigrade the PHASE transition occurs.

Discussion

113.	Dynamic equilibrium mainly concerns about_______________(a) spontaneous reactions(b) nonspontaneous reactions(c) reversible reactions(d) Irreversible reactionsI got this question in an international level competition.My question is based upon Equilibrium in Chemical Processes in section Equilibrium of Chemistry – Class 11
Answer» RIGHT answer is (d) IRREVERSIBLE reactions The best I can explain: In case of dynamic equilibrium, the ratio of REACTANTS and products changes. The NET change equals ZERO, as there is no net movement of particles. The formation of the reactants is equal to the formation of products here in dynamic equilibrium.

Discussion

114.	What is the reverse reaction of s of water?(a) conversion into ice(b) conversion into steam(c) conversion into water(d) equilibriaI have been asked this question by my college director while I was bunking the class.Origin of the question is Equilibrium in Chemical Processes in division Equilibrium of Chemistry – Class 11
Answer» The correct option is (C) CONVERSION into water The best explanation: The process of SOLIDIFYING of water is nothing but the formation of ICE that is a condensation of water the reverse reaction of condensation of water is the melting of water, that is the formation of water from ice.

Discussion

115.	In which of the following conditions do you think the rates of both forward and backward reactions are the same?(a) unstable equilibrium(b) not in an equilibrium(c) the beginning of a reaction(d) equilibriumThis question was posed to me in final exam.The origin of the question is Equilibrium in Chemical Processes topic in section Equilibrium of Chemistry – Class 11
Answer» Right choice is (d) equilibrium The BEST explanation: In a chemical reaction a state comes when both the forward and reverse reactions OCCUR at the same RATE and this state is KNOWN as equilibrium. At the beginning of the reaction, the rate of the Forward reaction is higher than the rate of BACKWARD reaction.

Discussion

116.	Equilibrium can be attained only from one side.(a) true(b) falseThis question was posed to me in an international level competition.My question is from Equilibrium in Chemical Processes in division Equilibrium of Chemistry – Class 11
Answer» Right option is (B) false For EXPLANATION: An EQUILIBRIUM can be obtained from both sides this is because a chemical reaction that reaches a state of dynamic equilibrium in which there are EQUAL rates of forwarding and backward reactions and there is no net change in composition.

Discussion

117.	At dynamic equilibrium the concentration of both the reactants and products are ____________(a) equal(b) not equal(c) cannot predict(d) sometimes equal sometimes not equalThis question was posed to me during an interview.My question comes from Equilibrium in Chemical Processes topic in portion Equilibrium of Chemistry – Class 11
Answer» Right option is (b) not equal To explain I would SAY: A dynamic EQUILIBRIUM in a chemical reaction, both forward and backward rates are always equal. As the reaction occurs the CONCENTRATION of product increases and the concentration of REACTANTS decrease at equilibrium they are not equal.

Discussion

118.	Synthesis of ammonia occurs through __________(a) Haber’s process(b) The carbon cycle(c) Nitrogen cycle(d) Hydrogen cycleI have been asked this question in an international level competition.My question is from Equilibrium in Chemical Processes topic in section Equilibrium of Chemistry – Class 11
Answer» The correct choice is (a) Haber’s process To explain: Haber’s process allows nitrogen from the AIR to COMBINE with hydrogen in order to FORM AMMONIA, this process is reversible and exothermic. This process occurs at high temperatures and a catalyst is a form of IRON.

Discussion

119.	What does the dotted curve in the diagram given below represent?(a) concentration of reactants(b) equilibrium constant(c) concentration of products(d) concentration of catalystThe question was asked in a job interview.The question is from Equilibrium in Chemical Processes topic in section Equilibrium of Chemistry – Class 11
Answer» CORRECT answer is (C) concentration of products Easiest explanation: The dotted curve in the above diagram the concentration of products as it is INCREASING with time and the attainment of equilibrium, the Strait curve is a concentration of REACTANTS as it is decreasing as the reaction proceeds.

Discussion

120.	When solid sugar dissolves in the solution __________ equilibrium is attained.(a) liquid vapor(b) solid liquid(c) solid vapor(d) noI had been asked this question in a national level competition.My question comes from Equilibrium in Physical Processes topic in division Equilibrium of Chemistry – Class 11
Answer» Correct option is (b) solid liquid The best explanation: When SUGAR, which is in solid form dissolves in a SOLVENT, forming sugar solution – a solid-liquid equilibrium is formed, where the rate of dissolution of sugar is EQUAL to the rate of CRYSTALLIZATION of sugar.

Discussion

121.	The equilibrium in a chemical reaction is represented by the symbol ____________(a) ↠(b) \(\Leftarrow\)(c) \(\rightleftharpoons\)(d) →The question was asked by my school teacher while I was bunking the class.I want to ask this question from Equilibrium in Physical Processes topic in division Equilibrium of Chemistry – Class 11
Answer» Correct choice is (c) \(\rightleftharpoons\) For explanation: The symbol that has both the left-sided harpoon and right-sided harpoon TOGETHER is a symbol USED for the equilibrium in a chemical reaction. It denotes that the BACKWARD and the forward RATES are equal and is REPRESENTED by the symbol “\(\rightleftharpoons\)”.

Discussion

122.	Select the correct equilibrium involving physical equilibrium.(a) it is possible only in a closed system at a given temperature(b) both forward and backward does not occur at the same rate(c) there is a dynamic but an unstable condition(d) measurable properties of the system do not remain constantThis question was addressed to me in a national level competition.The origin of the question is Equilibrium in Physical Processes topic in portion Equilibrium of Chemistry – Class 11
Answer» Right option is (a) it is possible only in a closed system at a given temperature The explanation is: The CORRECTED STATEMENTS of the wrong ones are that both backward and forward reactions OCCUR at the same rate in a stable CONDITION, while the measurable properties of the system REMAIN constant.

Discussion

123.	What will happen if the rate of evaporation is equal to the rate of condensation in the water?(a) solid-liquid equilibrium(b) liquid-vapor equilibrium(c) solid-vapor equilibrium(d) meltingThis question was addressed to me in homework.I want to ask this question from Equilibrium in Physical Processes in chapter Equilibrium of Chemistry – Class 11
Answer» Correct choice is (b) liquid-vapor EQUILIBRIUM For explanation I would say: When the rate of evaporation is equal to the rate of condensation water in the liquid phase and steam in vapor phase remained at equilibrium because its FORWARD rate of the REACTION and the backward rate of the reaction is the same at this PARTICULAR temperature.

Discussion

124.	Amount of a gas that is dissolved in a solvent depends on the pressure of the solvent.(a) True(b) FalseThe question was posed to me in unit test.The question is from Equilibrium in Physical Processes in section Equilibrium of Chemistry – Class 11
Answer» Correct option is (a) True To explain: The most common form of Henry’s LAW STATES that the partial pressure of the gas in the vapor phase is proportional to the mole FRACTION of the gas in a solution, therefore we can SAY that the above-given STATEMENT is true.

Discussion

125.	Which of the following statements is false regarding the equilibrium constant?(a) it has a definite value for every chemical reaction at a particular temperature(b) it is independent of initial concentrations of the reactants(c) it is dependent on the presence of a catalyst(d) if K is the equilibrium constant for a backward reaction then the forward reaction’s equilibrium constant is 1/kI got this question in an interview.Origin of the question is Equilibrium in Physical Processes in division Equilibrium of Chemistry – Class 11
Answer» RIGHT option is (C) it is dependent on the presence of a CATALYST Explanation: Equilibrium constant is independent of the presence of a catalyst, so the statement REGARDING the catalyst is wrong. A catalyst helps reaction to attain its equilibrium faster but does not alter the equilibrium constant.

Discussion

126.	Which of the following characteristics of chemical equilibrium is true?(a) equilibrium is dynamic in nature(b) equilibrium cannot be attained from either side(c) equilibrium cannot be obtained in a closed container(d) equilibrium state is affected by the presence of a catalystI got this question during an online exam.This interesting question is from Equilibrium in Physical Processes in section Equilibrium of Chemistry – Class 11
Answer» Right answer is (a) equilibrium is DYNAMIC in NATURE For EXPLANATION I would say: The CORRECT STATEMENTS of the wrong ones are; equilibrium can be attained from another side, the catalyst does not affect the equilibrium state and it can only be achieved in a closed container. Therefore equilibrium is dynamic in nature is the true characteristic of chemical equilibrium in the given options.

Discussion

127.	Which of the following is an example of solid-liquid equilibrium?(a) water and steam at hundred degrees centigrade(b) water and ice at 0-degree centigrade(c) the point where Ammonia is sublimized(d) boiling point of waterThe question was posed to me in class test.Asked question is from Equilibrium in Physical Processes topic in division Equilibrium of Chemistry – Class 11
Answer» Right answer is (b) water and ice at 0-degree centigrade To explain I would say: At zero degree centigrade, when water and ice are together the opposing PROCESS occurs SIMULTANEOUSLY at the same RATE, so the AMOUNT of Ice and water remains CONSTANT. It is an example of a solid-liquid equilibrium.

Discussion

128.	Physical equilibrium is the same as the chemical equilibrium.(a) true(b) falseThis question was addressed to me in semester exam.My question is based upon Equilibrium in Physical Processes topic in chapter Equilibrium of Chemistry – Class 11
Answer» Right ANSWER is (b) FALSE Easiest explanation: Equilibrium that is set up in a physical PROCESS LIKE the evaporation of water melting of solids is called physical equilibrium. If a reversible reaction is carried out in a closed vessel chemical equilibrium occurs when the rate of both the forward and BACKWARD reactions are equal, so the above statement is false.

Discussion

129.	If both the forward and reverse reaction rates are equal in the equilibrium is said to be ____________(a) dynamic equilibrium(b) equilibrium mixture(c) static equilibrium(d) newton equilibriumI had been asked this question in an interview for internship.Enquiry is from Equilibrium in Physical Processes in chapter Equilibrium of Chemistry – Class 11
Answer» The correct option is (a) dynamic equilibrium To explain I would say: When the reactants are KEPT in a closed VESSEL at a certain TEMPERATURE the concentration of reactants keep on decreasing while the concentration of products keep on increasing, at this STAGE when the rate of both the forward and the reverse reactions BECOME equal, it is said to be in a dynamic equilibrium.

Discussion

Explore topic-wise InterviewSolutions in .

Equilibrium of a reaction depends on the concentration of reactants.(a) true(b) falseThe question was posed to me during an interview.My question is taken from Equilibrium in Chemical Processes topic in chapter Equilibrium of Chemistry – Class 11

Equilibrium can be attained only from one side.(a) true(b) falseThis question was posed to me in an international level competition.My question is from Equilibrium in Chemical Processes in division Equilibrium of Chemistry – Class 11

Amount of a gas that is dissolved in a solvent depends on the pressure of the solvent.(a) True(b) FalseThe question was posed to me in unit test.The question is from Equilibrium in Physical Processes in section Equilibrium of Chemistry – Class 11

Physical equilibrium is the same as the chemical equilibrium.(a) true(b) falseThis question was addressed to me in semester exam.My question is based upon Equilibrium in Physical Processes topic in chapter Equilibrium of Chemistry – Class 11