If #2 L# of a gas at room temperature exerts a pressure of #72 kPa# on its container, what pressure will the gas exert if the container's volume changes to #7 L#?

1 Answer
Aug 3, 2016

Answer:

The new pressure is #21 kPa#

Explanation:

Let's begin by identifying our known and unknown variables.

The first volume we have is #2# L, the first pressure is #72kPa# and the second volume is #7#. Our only unknown is the second pressure.

The answer can be ascertained by using Boyle's Law:
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All we have to do is rearrange the equation to solve for the final pressure.

We do this by dividing both sides by #V_2# to get #P_2# by itself like this:
#P_2=(P_1xxV_1)/V_2#

Plug in your given values to get your final pressure:

#P_2=(72\kPa xx 2\ cancel"L")/(7\cancel"L")# = #21kPa#