Asample of a gas has a pressure of 248mm hg when the volume is 1.05l. what is the pressure of the gas when the volume is 3.98l?

So Boyle's Law equation is going to be used to solve this problem.

Boyle's Law: (P1)(V1)=(P2)(V2)

So, based on the question. Let's first note down what is given.

P1= 248mm Hg

V1= 1.05L

P2= ? (<-- What we are going to be solving for)

V2= 3.98L

Based on what we know, we can just simply plug it into the equation.

So...

1. (248 mmHg) (1.05L) = (P2) (3.98L)

2. (248 mm Hg) (1.05L)

       =     P2

        (3.98L)

3. P2 = 65.4 mm Hg is your answer

i believe you are right for all except the 3rd ( look at sqdancefan his answer is much better)