Browse by Stream
QnA
Home
QnA
Go To Your Study Dashboard

Get Answers to all your Questions

header-bg qa
  • Home
  • Engineering
  • of ethane undergoes combustion at <img alt="27^{\circ} \mathrm{C}" src="https://entranc

0.3 \mathrm{~g} of ethane undergoes combustion at 27^{\circ} \mathrm{C} in a bomb calorimeter. The temperature of calorimeter system (including the water) is found to rise by 0.5^{\circ} \mathrm{C}. The heat evolved during combustion of ethane at constant pressure is  ___________\mathrm{kJmol}^{-1}. (Nearest integer)
[Given : The heat capacity of the calorimeter system is 20 \mathrm{~kJ} \mathrm{~K}^{-1}, \mathrm{R}=8.3 \mathrm{JK}^{-1} \mathrm{~mol}^{-1}.
Assume ideal gas behaviour.
Atomic mass of \mathrm{C} and \mathrm{H} are 12 and 1 \mathrm{~g} \mathrm{~mol}^{-1} respectively]

Option: 1

1006


Option: 2

-


Option: 3

-


Option: 4

-


Answers (1)

best_answer

(Bomb calorimeter \rightarrow const volume Heat released By combustion of 1 mole

\begin{aligned} & \mathrm{C}_2 \mathrm{H}_6(\Delta \mathrm{U})=-\frac{20 \times .05}{0.3} \times 30=-1000 \mathrm{~kJ} \\ & \mathrm{C}_2 \mathrm{H}_6(\mathrm{~g})+7 / 2 \mathrm{O}_2(\mathrm{~g}) \rightarrow 2 \mathrm{CO}_2(\mathrm{~g})+3 \mathrm{H}_2 \mathrm{O}(\mathrm{l}) \\ & \Delta \mathrm{ng}=2-(2+7 / 2)=-(7 / 2) \\ & \Delta \mathrm{H}=\Delta \mathrm{U}+\Delta \mathrm{nRT} \\ & =-1000-7 / 2 \times 8.3 \times 300 \mathrm{~kJ} \\ & =-1000-6.225 \\ & =-1006 \mathrm{~kJ} \end{aligned}

So heat released =1006 \mathrm{~kJ} \mathrm{~mol}^{-1}

Posted by

Gaurav

View full answer

JEE Main high-scoring chapters and topics

Study 40% syllabus and score up to 100% marks in JEE

Similar Questions

Trending Articles/News

anam-khan

JEE Main 2025: 11 from Kota coaching centres among 24 students with 100 percentile
anam-khan

Low JEE Main rank? Explore alternative paths for engineering admission
anam-khan

Gender-gap in JEE Main 2025: Female participation remains around 31%, overall pool drops by 7.09%

Latest Question