WELCOME TO SaraNextGen.Com

Page No 111: - Chapter 4 - Chemical Kinetics - Intext Solutions - Ncert Solutions class 12 - Chemistry

Updated On 26-08-2025 By Lithanya


You can Download the Page No 111: - Chapter 4 - Chemical Kinetics - Intext Solutions - Ncert Solutions class 12 - Chemistry with expert answers for all chapters. Perfect for Tamil & English Medium students to revise the syllabus and score more marks in board exams. Download and share it with your friends

Question 4.5:

A first order reaction has a rate constant 1.15 10−3 s−1. How long will 5 g of this reactant take to reduce to 3 g?

Answer:

From the Question, we can write down the following information:

Initial amount = 5 g

Final concentration = 3 g

Rate constant = 1.15 10−3 s−1

We know that for a 1st order reaction,

https://img-nm.mnimgs.com/img/study_content/curr/1/12/17/263/6321/NCERT(INTEXT)_13-11-08_Utpal_12_Chemistry_4_9_html_m634877af.gif

= 444.38 s

= 444 s (approx)

Question 4.6:

Time required to decompose SO2Cl2 to half of its initial amount is 60 minutes. If the decomposition is a first order reaction, calculate the rate constant of the reaction.

Answer:

We know that for a 1st order reaction,

https://img-nm.mnimgs.com/img/study_content/curr/1/12/17/263/6322/NCERT(INTEXT)_13-11-08_Utpal_12_Chemistry_4_9_html_470b8c21.gif

It is given that t1/2 = 60 min

https://img-nm.mnimgs.com/img/study_content/curr/1/12/17/263/6322/NCERT(INTEXT)_13-11-08_Utpal_12_Chemistry_4_9_html_m2301ba1b.gif