Question

boyles law
boyles law states that the volume of a gas varies inversely with its pressure if temperature is held constant. (this means if one goes up, the other goes down.)
boyles law is: p1v1 = p2v2
solve the following problems (assume that temperature is constant).

1. a sample of oxygen gas occupies a volume of 250. ml at 740. torr pressure. what volume will it occupy at 800. torr pressure?
2. a sample of carbon dioxide occupies a volume of 3.50 liters at 125 kpa pressure. what pressure would the gas exert if the volume was decreased to 2.00 liters?
3. a 2.0 - liter container of nitrogen had a pressure of 3.2 atm. what volume would be neces to decrease the pressure to 1.0 atm?
4. ammonia gas occupies a volume of 450. ml at a pressure of 720. mmhg. what volur it occupy at standard pressure?
5. a 175 ml sample of neon had its pressure changed from 75 kpa to 150 kpa. what new volume?
6. chlorine gas occupies a volume of 1.2 liters at 720 torr pressure. wh will it occupy at 1 atm pressure?

Explanation:

Step1: Identify given values and formula

We use Boyle's Law $P_1V_1 = P_2V_2$.

Step2: Solve for unknown variable

For each problem, we re - arrange the formula $V_2=\frac{P_1V_1}{P_2}$ (when solving for volume) or $P_2=\frac{P_1V_1}{V_2}$ (when solving for pressure).

Problem 1

$P_1 = 740$ torr, $V_1=250$ mL, $P_2 = 800$ torr.
$V_2=\frac{P_1V_1}{P_2}=\frac{740\times250}{800}=231.25$ mL

Problem 2

$P_1 = 125$ kPa, $V_1 = 3.50$ L, $V_2=2.00$ L.
$P_2=\frac{P_1V_1}{V_2}=\frac{125\times3.50}{2.00}=218.75$ kPa

Problem 3

$P_1 = 3.2$ atm, $V_1 = 2.0$ L, $P_2 = 1.0$ atm.
$V_2=\frac{P_1V_1}{P_2}=\frac{3.2\times2.0}{1.0}=6.4$ L

Problem 4

Standard pressure $P_2 = 760$ mmHg, $P_1 = 720$ mmHg, $V_1 = 450$ mL.
$V_2=\frac{P_1V_1}{P_2}=\frac{720\times450}{760}\approx426.32$ mL

Problem 5

$P_1 = 75$ kPa, $V_1 = 175$ mL, $P_2 = 150$ kPa.
$V_2=\frac{P_1V_1}{P_2}=\frac{75\times175}{150}=87.5$ mL

Problem 6

$1$ atm = 760 torr, $P_1 = 720$ torr, $V_1 = 1.2$ L, $P_2 = 760$ torr.
$V_2=\frac{P_1V_1}{P_2}=\frac{720\times1.2}{760}\approx1.13$ L

Answer:

1. $231.25$ mL
2. $218.75$ kPa
3. $6.4$ L
4. $\approx426.32$ mL
5. $87.5$ mL
6. $\approx1.13$ L