A. Both forward and backward reactions will be exothermic
B. Neither of the reactions will be endothermic
C. The combination reaction will be exothermic, while the dissociation reaction will be
endothermic
D. The combination reaction will be endothermic, while the dissociation reaction will be
exothermic
Related Mcqs:
- Rate constant for a first order reaction does not depend upon reaction time, extent of reaction and the initial concentration of reactants; but it is a function of reaction temperature. In a chemical reaction, the time required to reduce the concentration of reactant from 100 gm moles/litre to 50 gm moles/litre is same as that required to reduce it from 2 gm moles/litre to 1 gm mole/litre in the same volume. Then the order of this reaction is ?
A. 0
B. 1
C. 2
D. 3 - In a chemical reaction, represented by as shown in the bellow figure, it is observed that the (i) Rate of reaction increases by a factor of 4 on doubling the concentration of the reactant. (ii) Rate of reaction increases by a factor of 9 on trebling the concentration of the reactant. Then the rate of the reaction is proportional to(where, CA = concentration of the reactant)_____________________?
A. CA
B. CA2
C. CA3
D. CA4 - For a vapour phase catalytic reaction (A + B → P) which follows the Ridel mechanism and the reaction step is rate controlling, the rate of reaction is given by (reaction rate is irreversible, product also absorbs) ?
A. -rA = (k . PA . PB)/(1 + KAPA + KPPP)
B. -rA = (k . PA
2 – k1PP)/(1 + KAPA + KPPP)
C. -rA = (k . PA . PB)/(1 + KAPB + KBPB . KPPP)
D. -rA = (k . PA . PB)/(1 + KAPA) - For the chemical reaction P → Q, it is found that the rate of reaction doubles as the concentration of ‘P’ is doubled. If the reaction rate is proportional to Cp n, then what is the value of ‘n’ for this chemical reaction ?
A. 0
B. 1
C. 2
D. 3 - The irreversible reaction, X → Y, is the special case of the reversible reaction, X ⇌ Y, in which the _____________________?
A. Equilibrium constant is infinite
B. Fractional conversion of ‘A’ at equilibrium is unity
C. Concentration of ‘A’ at equilibrium is zero
D. All A., B. and C. - The irreversible reaction is a special case of reversible reaction, if the________________?
A. Equilibrium constant is 1
B. Conversion of the reactant at equilibrium condition is zero
C. Reactant concentration at equilibrium condition is zero
D. All A., B. and C. - An isothermal aqueous phase reversible reaction, P ⇌ R, is to be carried out in a mixed flow reactor. The reaction rate in k.mole/m3 .h is given by, r = 0.5CP – 0.125CR. A stream containing only P enters the reactor. The residence time required (in hours) for 40% conversion of P is_________________?
A. 0.80
B. 1.33
C. 1.60
D. 2.67 - The rate expression for a heterogeneous catalytic reaction is given by, – rA = K.KA PA(1 + KA.PA + KR.PR), where K is surface reaction rate constant and KA and KR are absorption equilibrium constants of A and R respectively. If KR PR >> (1 + KA PA), the apparent activation energy EA is equal to (given E is the activation energy for the reaction and ΔHR and ΔHA are the activation energies of adsorption of R and A) ?
A. E
B. E + ΔHA
C. E + ΔHA – ΔHR)
D. ΔHA + ΔHR - Overall rate of reaction in a heterogeneous catalytic reaction depends upon the mass and energy transfer from the fluid to solid surface and its rate of reaction is usually ________________ the concentration of catalyst, if it does not entail a chain mechanism?
A. Proportional to
B. Independent of
C. Inversely proportional to
D. Proportional to the square of - A reaction in which one of the products of reaction acts as a catalyst is called a/an ______________ reaction?
A. Catalytic
B. Autocatalytic
C. Photochemical
D. None of these