1. What is the pressure on 2.5 L, if the initial pressure was 400 mmHg and the
initial volume was 1.75 L? *

The answer to your question is   P2 = 280 mmHg

Explanation:

Data

Pressure 1 = P1 = 400 mmHg

Volume 1 = V1 = 1.75 L

Pressure 2 = ?

Volume 2 = 2.5 L

Process

1.- Use Boyle's law to solve this problem

                  P1V1 = P2V2

-Solve for P2

                     P2 = P1V1 / V2

2.- Substitution

                    P2 = (400)(1.75) / 2.5

3.- Simplification

                   P2 = 700 / 2.5

4.- Result

                   P2 = 280 mmHg