K L Chugh Solutions for Chapter: Chemical Kinetics, Exercise 6: Follow Up Problems

Author:K L Chugh

K L Chugh Chemistry Solutions for Exercise - K L Chugh Solutions for Chapter: Chemical Kinetics, Exercise 6: Follow Up Problems

Attempt the practice questions on Chapter 4: Chemical Kinetics, Exercise 6: Follow Up Problems with hints and solutions to strengthen your understanding. NEW SYSTEMATIC MODERN CHEMISTRY solutions are prepared by Experienced Embibe Experts.

Questions from K L Chugh Solutions for Chapter: Chemical Kinetics, Exercise 6: Follow Up Problems with Hints & Solutions

HARD
12th West Bengal Board
IMPORTANT

For the thermal decomposition of azomethane, CH3 N2CH3 at 600 K to N2 and C2H6

t(sec)010002000PA(10-2torr)8.205.723.99 300040002.781.94

where PA is the partial pressure of azomethane. Show that the decomposition is a first order reaction and find the rate constant.

HARD
12th West Bengal Board
IMPORTANT

The following data were obtained during the first order thermal decomposition of N2O5g at constant volume: 2 N2O5g2 N2O4g+O2g

S. No. Time/s Total pressure/atm
1. 0 0.5
2. 100 0.512

Calculate rate constant.

HARD
12th West Bengal Board
IMPORTANT

Hydrolysis of methyl acetate in aqueous solution has been studied by titrating the liberated acetic acid against sodium hydroxide. The concentration of the ester at different times is given below:

t/min 0 30 60 90
C/molL-1 0.8500 0.8004 0.7538 0.7096

Show that it follows a pseudo first order reaction, as the concentration of water remains nearly constant 55 mol L-1 during the course of the reaction. What is the value of k' in this equation? Rate =k'CH3COOCH3H2O

[Hint. k=k'H2O=2.303tlogC0Ct]

HARD
12th West Bengal Board
IMPORTANT

The kinetics of hydrolysis of methyl acetate in excess of hydrochloric acid solution at 298 K were followed by withdrawing 2 mL of the reaction mixture at intervals of time (t), adding 50 mL of water and titrating against baryta-water. The following results were obtained:

tmin 0 10 28 58 115
Titre (mL) 18.5 19.1 20.1 21.6 24.6 34.8

Determine the velocity constant of the hydrolysis.

[Hint. Substitute a=34.8-18.5=16.3, and a-x=(34.8-19.1), 34.8-20.1,34.8-21.6,34.8-24.6 att=10, 28, 58 and 115 respectively in k=2.303/t log a/a-x and get k]