Answer
0.50 L
Work Step by Step
Let $P_{1}$ = 0.80 atm , $V_{1}$ = 0.25 L, $P_{2}$ = 0.4 atm & $V_{2}$ = ?
Using gas Law Equation $P_{1}V_{1}=P_{2}V_{2}$, we have:
0.80 atm x 0.25 L = 0.4 atm x $V_{2}$
$V_{2}$ = 0.89 atm / 0.4 atm x 0.25 L
= 0.50 L