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Right answer is (d) H2O + H2O \(\rightleftharpoons\)H3O^+ + OH^–

For EXPLANATION I would say: Only H2O + H2O \(\rightleftharpoons\)H3O^+ + OH^– is in ionic EQUILIBRIUM. As the equilibrium established between the UNIONIZED molecules and the IONS in the solution of WEAK electrolytes is known as Ionic Equilibrium.

The correct answer is (c) sound

Explanation: Values of the degree of dissociation or degree of ionization DEPENDS upon the following factors: 1) the nature of the solute, 2) the nature of the solvent 3) CONCENTRATION and 4) temperature of the solution.

Right CHOICE is (a) 1

To explain: Degree of dissociation is the FRACTION of the TOTAL number of molecules which dissociate into constituent ions, it is represented by the symbol ɑ. As a strong electrolyte dissociate completely, it VALUES is 1.

The correct choice is (a) do not conduct

Best EXPLANATION: Aqueous solution of SUGAR does not conduct electricity, but Aqueous solution of sugar CONDUCTS electricity. This is because the aqueous solution of sugar is a NONELECTROLYTE, whereas the salt solution is an electrolyte.

Right option is (a) weak

The best I can explain: Electrolytes which dissociate into a lesser extent in aqua SOLUTION are called weak electrolytes. All organic acids except sulfonic acids and BASES like Ammonia, Ammonium hydroxide, AMINES,etc are weak electrolytes.

Right answer is (d) ammonia

The EXPLANATION: Electrolytes which dissociate ALMOST COMPLETELY into constituent ions in aqueous SOLUTIONS are known as strong electrolytes. THEREFORE ammonia is not a strong electrolyte because it can’t dissociate completely.

Correct OPTION is (a) true

The best explanation: If keeping the volume of the SYSTEM constant and INERT GASES ADDED the relative molar concentration of the substance will not change hence the equilibrium position of the reaction remains unaffected.

The correct CHOICE is (a) IONIC EQUILIBRIUM

The best explanation: The equilibrium that is attained between the ionized molecules and the ions in the solution of weak electrolyte is called Ionic Equilibrium. CH3COOH \(\rightleftharpoons\) CH3COO^– + H^+ is an example; CH3COO^– and H^+ are ions.

Correct CHOICE is (a) shifts left

Easiest explanation: According to Le chatelier’s PRINCIPLE if at EQUILIBRIUM the concentration of one of the products is INCREASED the equilibrium will shift in the backward direction that is towards the left side and vice versa.

Correct ANSWER is (a) HIGH

The EXPLANATION: When the process is exothermic, low temperature of FAVORS Forward reaction and when the process is ENDOTHERMIC high temperature favors the formation of the products. This is according to le chatelier’s principle.

The correct option is (d) does CHANGE the position

Explanation: As per Le chatelier’s principle on the EFFECT of catalyst states that the PRESENCE of the catalyst does not change the position of the EQUILIBRIUM it simply fast and the ATTAINMENT of the equilibrium.

The correct option is (b) increase in the number of moles

The BEST I can explain: At constant pressure, if INERT gas added, it will increase the volume of the system there for the equilibrium will shift in a direction, in which there is an increase in the number of moles of GASES as PER le chatelier’s principle.

The correct option is (a) EXOTHERMIC

Easy explanation: If a reaction releases heat then it is exothermic in NATURE and if the reaction CONSUMES heat it is endothermic in nature. An example of the exothermic reaction is the mixing of WASHING SODA in water and mixing glucose in water is an example of an endothermic reaction.

The correct CHOICE is (a) it moves backward direction

To explain I WOULD say: When there is a change in a number of moles, the equilibrium will shift in the direction having a SMALLER number of moles when the pressure is INCREASED and vice-versa. Here the equilibrium moves in the backward direction because the reactants have less number of moles than products.

Correct option is (c) there is no change in equilibrium

To explain I would SAY: According to LE chatelier’s principle, there will be no effect of PRESSURE on equilibrium if the chemical equation has the same number of moles of reactants and products hear the moles on the left side is equal to the moles on the right side that is 2.

The correct ANSWER is (a) equilibrium will shift in the FORWARD direction

To explain: As per the Le chatelier’s principle, if the concentration of ONE of the reactants is increased at equilibrium the equilibrium will shift in the forward direction and vice versa is also possible. Therefore we can say that there is an EFFECT of change of concentration on equilibrium.

Right answer is (d) color

The explanation is: According to Le chatelier’s principle, if a SYSTEM at equilibrium is SUBJECTED to a change in CONCENTRATION, pressure or temperature the equilibrium SHIFTS in the direction that tends to NULLIFY the effect of the change.

Correct ANSWER is (c) the reaction REACHES EQUILIBRIUM

Explanation: When Gibbs free ENERGY is zero, the reaction reaches equilibrium and at equilibrium, the reaction quotient is replaced by the equilibrium constant, as both the values are equal. That is when reaction quotient is equal to the equilibrium constant reaction reaches equilibrium.

Correct choice is (b) 8.314J mol^–1K^–1

Easiest EXPLANATION: THOUGH the TEMPERATURE is not given, UNIVERSAL gas CONSTANT value always remains the same, whatever may be the other values. So the universal gas constant is given by a constant value that is -8.314J mol^–1K^–1.

The correct CHOICE is (b) nonspontaneous

For explanation: Is the value of Gibbs free energy for a REACTION is 20 J/mol, that MEANS it is positive,-ΔG0/RT is NEGATIVE and that e^-ΔG0/RT is greater than 1, so the K is greater than 1 this means the reaction is nonspontaneous.

The correct option is (B) K is less than 1

Easiest explanation: If the VALUE of Gibbs free ENERGY is GREATER than the zero that means, -ΔG0/RT is negative and that e^-ΔG0/RT is greater than 1, so the K is greater than 1 this means the reaction is nonspontaneous and proceeds in the forward direction.

Right CHOICE is (b) REACTION quotient

The BEST explanation: In the EQUATION ΔG = ΔG0 + RT lnQ, ΔG is the Gibbs free energy, R is the universal gas constant, T is the temperature and Q is the reaction quotient. When Gibbs free energy is zero, the reaction quotient becomes EQUILIBRIUM constant.

The CORRECT answer is (a) Gibbs FREE energy is POSITIVE

Explanation: When Gibbs free energy is positive, the reaction that occurs is nonspontaneous and a reaction occurs BACKWARD that is the products are converted into reactants. SIMPLY the reverse reaction could occur.

The correct option is (c) 100 k

The BEST I can EXPLAIN: We know that ΔG0 = – RT LNKC, where ΔG0 is the standard Gibbs free energy, R is universal GAS constant, T is the temperature and KC is equilibrium constant; substituting ΔG0 as -2502 J/mol, we get -2502 J/mol = -8.314J mol^–1K^–1 × T ln2 = 2502 J/mol = T = 2502/2.502 = 100 k.

Right answer is (d) 2.7

The explanation is: We know that ΔG0 = – RT lnKc, where ΔG0 is the STANDARD Gibbs free energy, R is UNIVERSAL gas constant, T is the temperature and KC is EQUILIBRIUM constant; substituting ΔG0 as-831.4 J/mol, we get LNK = -831.4J/mol divided by -8.314J mol^–1K^–1 × 100K = 1; lnk = 1; K = e^1 = 2.7

The correct choice is (b) – 7.64 × 10^4 J mol^–1

For explanation I WOULD say: We know that ΔG0 = – RT lnKc, where ΔG0 is the standard Gibbs free energy, R is universal gas CONSTANT, T is the temperature and KC is equilibrium constant; substituting KC as 2 x 10^13, ΔG0 = (– 8.314J mol^–1K^–1 × 300K) × ln(2×10^13); ΔG0 = – 7.64 × 10^4 J mol^–1.

The correct choice is (d) reaction quotient increases

To explain I would say: In a reaction, if reaction quotient is less than the equilibrium CONSTANT, the reaction quotient will tend to increase and the reaction will proceed in the FORWARD direction TILL it reaches equilibrium.

The correct answer is (a) QC DECREASES till equilibrium

The explanation is: If QC > KC, the value of QC will tend to decrease to REACH the value of equilibrium constant (that is towards equilibrium) and the REACTION will continue in the opposite DIRECTION, where QC is reaction quotient and KC is the equilibrium constant.

Right ANSWER is (b) QC

Easy EXPLANATION: For any reversible REACTION at any stage other than EQUILIBRIUM, the ratio of the molar concentrations of the products to that of the reactants, where is concentration TERM is raised to the power equal to the stoichiometric efficient to the substance concerned is called the reaction quotient, QC.

Correct OPTION is (d) dynamic equilibrium

For explanation I would say: If KC > 10^-3, the reactants are predominant over the PRODUCTS in a CHEMICAL reaction and the products are predominant, over the reactants in a chemical reaction, ifKC > 10^3, where KC is the equilibrium constant.

Right choice is (b) 3

To EXPLAIN I would say: If KC > 10x, the products are PREDOMINANT, over the reactants in a chemical reaction because if KC is very large the reaction proceeds nearly to completion an example for this is at 300K,H2(g) + Cl2(g) \(\rightleftharpoons\) 2HCL(g), KC = 4 X 10^31.

Right choice is (a) [AgNO3(aq)]^2/[HNO3(aq)]^2

To explain: It is important that for the EXISTENCE of HETEROGENEOUS equilibrium pure solid or liquid must also be at equilibrium, but their concentrations do not APPEAR in the expression of the equilibrium CONSTANT. So here KC = [AgNO3(aq)]^2/[HNO3(aq)]^2.

Right choice is (b) heterogeneous EQUILIBRIUM

Easy explanation: In heterogeneous equilibrium, the reactants and PRODUCTS are present in two or more physical States or phases. Here carbon DIOXIDE is present in the GASEOUS state while carbon is present in the solid state, so it is an example of heterogeneous equilibrium.

The CORRECT choice is (d) 2 x 10^-3

For EXPLANATION: As we know that KC = KP(RT)^Δng, here Δng = moles of PRODUCTS – moles of reactants which are in gaseous state only = 2 – (1+1) = 0. So KC = KP(RT)^0, KC = KP(1) = KP; KC = KP, therefore KP is same as KC and KP is 2 x 10^-3.

Correct answer is (c) KC = KP(RT)^Δng

The explanation is: For example, take the reaction 2HBr(g) \(\leftrightarrow\) H2(g) + Br2(g), KC = [H2][Br2]/[HBr]^2; KP = [pH2][pBr2]/[pHBr]^2, where pH2 = [H2]RT, pBr2 = [Br2]RT and [pHBr] = [HBr]RT. So we can SAY that KC = KP(RT)^Δng, where Δng = moles of products – moles of reactants which are in GASEOUS state only.

The correct choice is (a) true

To EXPLAIN I would say: We have P = CRT e where p is PRESSURE, R is a universal CONSTANT and T is the temperature, we derive the equation from the ideal gas equation PV=nRT. So from P = CRT, we can say that at a constant temperature the pressure is directly proportional to the concentration of the gas.

The correct answer is (a) homogeneous chemical equilibrium

The explanation: In homogeneous equilibrium, the REACTANTS and PRODUCTS are present in the same phase or physical state. Nitrogen, OXYGEN, and nitrogen monoxide are present in a gaseous state, so it is homogeneous chemical equilibrium.

The correct answer is (B) false

To elaborate: The units of KP are (atm)^Δng and the units of KC are (mol/L)^Δng. Where Δng = moles of products – moles of reactants which are in the gaseous STATE only. As the units of KP and KC are not equal the above STATEMENT is considered to be false.

Right choice is (b) not in both Homogeneous and heterogeneous EQUILIBRIUM

For explanation: As we know that in Homogeneous equilibrium the REACTANTS and PRODUCTS are present in the same PHASE or physical state but here it is in a liquid state and gaseous state, so it is not in Homogeneous equilibrium.