Question

a container of 2.00 moles of an ideal gas as 1000 K undergoes a constant pressure and volume process in which the number of moles is increased to 5moles. what is the final temperature of the gas.

How do I start this? Do I somehow use the ideal gas law?

Answer 1

Use PV=nRT

so R=P1V1/n1T1

and R=P1V1/n2T2

R=P1V1/n1T1=P1V1/n2T2

n1T=n2T2

Answer 2

I got the answer to be 400. But can you explain to me those formulas? I'm still a bit confuse on how you got them. Where do these P1 and P2 and T1 and T2 come from

Answer 3

The original formula is

PV=nRT

for the question given we have a set of starting conditions

P=P1
V=V1
n=n1
T=T1

hence

P1 x V1=n1 x R x T1

which rearranges to

R=P1V1/n1T1

the second set of conditions is

P=P1
V=V1
(because P1 and V1 are constant in the question)
T=T2
N=n2

so

R=P1V1/n2T2

as R is the same in both cases

R=P1V1/n1T1=P1V1/n2T2

which rearranges to

n1T=n2T2