100.0mL of gas at 25.0 DC and 1.0 atm changes to 50.0 DC at 1 atm. What is the new volume of gas?

The new volume is 108.4 mL

Explanation:

When pressure remains constant, volume changes directly proportional to absolute T°

V1 / T1 = V2 / T2

Let's convert DC to absolute T°

25 DC + 273 = 298K

50 DC + 273 = 323K

100 mL/298K = V2 / 323K

(100 mL/298K). 323K = V2

108.4 mL = V2