Question

A gas has a volume of 350 mL at 318.15 K. If the volume changes to 4.00 L, what is the new temperature?

Answer 1

28°C.
Explanation:
The correct equation to use with these kinds of questions is the Combined Gas Law.
P
1
⋅
V
1
T
1
=
P
2
⋅
V
2
T
2
This equation, though, is a little unnecessary at times because of the possibility of extra constants.
In this case you have a pressure constant which enables us to shorten your longer equation down to Charles' Law because pressure remains the same and doesn't affect the calculation.
V
1
T
1
=
V
2
T
2
The next step is to isolate the variable that you want, which is, in this case,
T
2
.
T
2
=
V
1
T
1
V
2
Now it is time to replace your known variables with numbers
T
2
=
350
m
L
⋅
45
°
C
400
m
L
And calculate...
T
2
=
28.125
°
C
Significant digits...
T
2
=
28
°
C