Answer:
![\boxed {\boxed {\sf 4.45 \ atmospheres}}](https://tex.z-dn.net/?f=%5Cboxed%20%7B%5Cboxed%20%7B%5Csf%204.45%20%5C%20atmospheres%7D%7D)
Explanation:
We are asked to find the pressure given a change in volume. The temperature remains constant, so we are only concerned with volume and pressure. We will use Boyle's Law, which states the volume of a gas is inversely proportional to the pressure. The formula for this law is:
![P_1 V_1= P_2V_2](https://tex.z-dn.net/?f=P_1%20V_1%3D%20P_2V_2)
The initial pressure is unknown, but the volume starts at 55.2 liters.
![P_1 * 55.2 \ L = P_2V_2](https://tex.z-dn.net/?f=P_1%20%2A%2055.2%20%5C%20L%20%3D%20P_2V_2)
The volume is reduced to 28.8 liters and the pressure is 8.53 atmospheres.
![P_1 * 55.2 \ L = 8.53 \ atm * 28.8 \ L](https://tex.z-dn.net/?f=P_1%20%2A%2055.2%20%5C%20L%20%3D%208.53%20%5C%20atm%20%2A%2028.8%20%5C%20L)
We are solving for the initial pressure, so we must isolate the variable P₁. It is being multiplied by 55.2 liters. The inverse operation of multiplication is division, so we divide both sides of the equation by 55.2 L.
![\frac {P_1 * 55.2 \ L }{55.2 \ L}= \frac{8.53 \ atm * 28.8 \ L}{55.2 \ L}](https://tex.z-dn.net/?f=%5Cfrac%20%7BP_1%20%2A%2055.2%20%5C%20L%20%7D%7B55.2%20%5C%20L%7D%3D%20%5Cfrac%7B8.53%20%5C%20atm%20%2A%2028.8%20%5C%20L%7D%7B55.2%20%5C%20L%7D)
![P_1= \frac{8.53 \ atm * 28.8 \ L}{55.2 \ L}](https://tex.z-dn.net/?f=P_1%3D%20%5Cfrac%7B8.53%20%5C%20atm%20%2A%2028.8%20%5C%20L%7D%7B55.2%20%5C%20L%7D)
The units of liters (L) cancel.
![P_1= \frac{8.53 \ atm * 28.8 }{55.2}](https://tex.z-dn.net/?f=P_1%3D%20%5Cfrac%7B8.53%20%5C%20atm%20%2A%2028.8%20%7D%7B55.2%7D)
![P_1=\frac{245.664 }{55.2 } \ atm](https://tex.z-dn.net/?f=P_1%3D%5Cfrac%7B245.664%20%7D%7B55.2%20%7D%20%5C%20atm)
![P_1 = 4.45043478261 \ atm](https://tex.z-dn.net/?f=P_1%20%3D%204.45043478261%20%5C%20atm)
The original measurements of volume and pressure have 3 significant figures, so our answer must have the same. For the number we calculated, that is the hundredths place. The 0 in the thousandths place tells us to leave the 5.
![P_1 \approx 4.45 \ atm](https://tex.z-dn.net/?f=P_1%20%5Capprox%204.45%20%5C%20atm)
The initial pressure inside the container is approximately <u>4.45 atmospheres.</u>