Question

A certain amount of an ideal monatomic gas needs
20 J of heat energy to raise its temperature by
10°C at constant pressure. The heat needed for the
same temperature rise at constant volume will be
(1) 30 J
(2) 12 J
(3) 200 J
(4) 215.3 J​

Answer 1

Answer:

2

Explanation:

Since the gas is monoatomic

⇒C

v= 2

3R

and C

p

=

2

5R

Now,

Let the no of moles of has =n moles

We know that,

at constant pressure

ΔQ=nC

p

ΔT

⇒20=n×

2

5R

×10

⇒n=

5R

4

and, at constant volume

ΔQ=nC

v

ΔT

putting the values of n and ΔT,C

v

ΔQ=

5R

4

×

2

3R

×10

⇒ΔQ=12 J

Answer 2

A certain amount of an ideal monatomic gas needs 20 J of heat energy to raise its temperature by 100C at constant

akka 200j is the correct answer