Is this correct use of the formula? (Pressure, Volume and Temperature)

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Homework Statement



A quantity of gas occupies a volume of 0.5m. The pressure of the gas is 300kPa, when its temperature is 30°C. Calculate the pressure of the gas if it is compressed to half of its volume and heated to a temperature of 140°C.

Homework Equations



(P1 x V1)/T1 = (P2 x V2)/T2

The Attempt at a Solution



P1 = 300 kPa
V1 = 0.5m (im not sure what unit of volume I am meant to be using or converting to so I am using as it is)
T1 = 30°C (303 Kelvin)
P2 = THIS IS WHAT I NEED TO FIND OUT
V2 = 0.25m
T2 = 140°C (413 Kelvin)

I moved stuff around to make V2 after the "=" Is this right?
= (300x0.5)/303 = (P2 x 0.25m)/413
= (300x0.5)/303/0.25x413 = 817.82kPa?
if not any suggestions?
 
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Yes exactly right.

You need to be careful with calcs like "(300x0.5)/303/0.25" your caclulator might not do them in the order you think.

It might be safer to do something like:
P1V1/T1 = P2V2/T2
so P2 = P1(V1/V2) * (T2/T1)
this also makes it obvious that units of the answer are correct.