Answer
(a) 52.4 L
(b) 25 L
(c) 100. L
(d) 44.7 L
Work Step by Step
1. Conversion factors:
$1 \space atm = 760 \space mmHg (exact)$
$1 \space mmHg = 1 \space Torr$
2. According to the Boyle's Law:
$$P_1V_1 = P_2V_2 \longrightarrow \frac{P_1V_1}{P_2} = V_2$$
(a) $$V_2 = \frac{(760. \space mmHg)(50.0 \space L)}{725 \space mmHg} = 52.4 \space L$$
(b)
$P_2 = 2.0 \space atm \times \frac{760 \space mmHg}{1 \space atm} = 1500 \space mmHg$
$$V_2 = \frac{(760. \space mmHg)(50.0 \space L)}{1500 \space mmHg} = 25 \space L$$
(c)
$P_2 = 0.500 \space atm \times \frac{760 \space mmHg}{1 \space atm} = 380 \space mmHg$
$$V_2 = \frac{(760. \space mmHg)(50.0 \space L)}{380 \space mmHg} = 100. \space L$$
(d)
$P_2 = 850 \space Torr \times \frac{1 \space mmHg}{1 \space Torr} = 850 \space mmHg$
$$V_2 = \frac{(760. \space mmHg)(50.0 \space L)}{850 \space mmHg} = 44.7 \space L$$
