CameraIcon
CameraIcon
SearchIcon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

Assign the sign of work done (based on SI convention) in the following chemical changes taking place against the external atmospheric pressure:
(I) N2(g)+3H2(g)2NH3(g)
(II) NH4HS(s)NH3(g)+H2S(g)
(III) C(s)+CO2(g)2CO(g)
(IV) C2H6(g)+3.5O2(g)2CO2(g)+3H2O(l)

A
I II III IV
+ +
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
B
I II III IV
+ +
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
I II III IV
+ 0 +
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
I II III IV
+ 0
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is A I II III IV
+ +
ng= moles of gaseous products - moles of gaseous reactants
If ng=+ve - expansion
If ng=ve - contraction.
work of Expansion is -ve
Work of contration is +ve

For reaction 1,
ng=2(3+1)=2=ve - contraction, which means +ve work.

For reaction 2,
ng=1+1(0)=2=+ve - expansion, which means -ve work.

For reaction 3,
ng=2(1)=1=+ve - expansion, which means -ve work.

For reaction 4,
ng=2(4.5)=2.5=ve - contraction, which means +ve work.

So, The work done in the reaction 1, 2, 3 and 4 is + , - , - , + respectively.

flag
Suggest Corrections
thumbs-up
1
Join BYJU'S Learning Program
Join BYJU'S Learning Program
CrossIcon