Rate of a Chemical Reaction

IMPORTANT

Rate of a Chemical Reaction: Overview

This Topic covers sub-topics such as Rate of a Chemical Reaction, Units of Rate Constant, Average Rate of a Reaction, Instantaneous Rate of a Reaction, Rate Constant of a Chemical Reaction and, Difference between Rate Law and Law of Mass Action

Important Questions on Rate of a Chemical Reaction

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The sum of the powers of the concentration terms in the experimentally determined rate equation is known as:

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Consider a reaction a G + bH products .  When concentration of both the reactants G and H is doubled, the rate increases by eight times. However, when the concentration of G is doubled, keeping the concentration of H constant, the rate is doubled. The overall order of the reaction is:

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Consider the chemical reaction:

     N 2 g + 3 H 2 g 2 NH 3 g

The rate of this reaction can be expressed in terms of time derivatives of concentration of  N2g , H2g  and  NH3g Identify the correct relationship amongst the rate expressions:

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Hydrogen gas, H2(g), reacts with iodine gas, I2(g), to form hydrogen iodide, HI(g):

H2(g) + I2(g)  2HI(g)

The mechanism of the two-step reaction is considered to be:

step 1: I2(g) k-1k1 2I(g)                        fast

step 2: 2I(g) + H2(g) k2 2HI(g)     slow

What is the rate equation for the overall reaction?

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For a reaction 1/2 A2 B, rate of disappearance of A is related to rate of appearance of B by the expression

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Equilibrium constants NO(g)+1/2O2K1NO2( g) and 2NO2(g)K22NO(g)+O2( g) for the following equilibria

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Ammonia and oxygen react at high temperature as;
4NH3g+5O2(g)4NO(g)+6H2O(g)

In an experiment rate of formation NO is 3.6×10-3 mol L-1 s-1. Calculate rate of disappearance of ammonia.

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_____ (Law of mass action/Rate law) is an equation which represents the ratio between the masses of products and masses of reactants whose power is raised according to their stoichiometric coefficients.

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For a reaction
NO2+COCO2+NO the possible elementary steps (below 500 K are
Step 1:NO2+NO2 slow NO+NO3
Step 2:NO3+CO Fast CO2+NO2
its rate expression will be

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For a given reaction 3A +BC+D the rate of reaction can be represented by

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The term -dcdt in a rate equation refers to:

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Thermal decomposition of N2O5 occurs as per the equation below :

2N2O54NO2+O2

The correct statement is

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The rate constnat for the reaction

2 N2O54NO2+O2

is 3.0×10-5sec-1. if the rate is 2.4×10-5 mol litresec-1-1, then the concentration of N2O5 (in mol litre -1 ) is

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Rate constant depends upon:

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The rate constant of the reaction AB is 0.5×10-3M sec-1. What is the concentration of B after 10 min from the start of the reaction?
 

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For the reaction, 2SO2+O22SO3, the rate of disappearance of O2 is 2×10-4 mol L-1 s-1 . The rate of appearance of SO3 is

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For a reaction: N2+3H22NH3, the rate of reaction with respect to NH3will be:

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For the reaction, N2+3H22NH3, if dNH3dt=2×10-4 mol/L/s, the value of -dH2dt would be

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Nitrogen tetraoxide  N2O4 decomposes as
                   N2O4g2 NO2g

If the pressure of N2O4 falls from 0.50 atm to 0.32 atm in 30 minutes, the rate of appearance of NO2g is:

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What is a rate constant?