pressure temp and volume

[spoog74]

---

Members do not see this ad.

i had this down before but im not sure why in the world i forgot;

can someone xplain this

If the pressure on a gas sample is quartered, while the absolute temp is doubled, by what factor will the volume change assuming the moles are constant?

the answer is 8 but id like to know the reasoning please

i know it has something to do with pv=nrt

 

[justdandi]

When n is constant, the expression is PV/T.

There's an inverse relationship between P and V. So when P is quartered (x1/4), V is quadrupled (x4).

There's a directly proportional relationship between V and T. So when T is doubled (x2), V is doubled (x2).

4 x 2 = 8

 

[jas1317]

rearranging PV=nRT……V=T/P(since n is constant)……V=2*T/(1/4)*P…….to get the fraction out of the denominator you must flip it(1/4 flipped to 4/1) and multiply it by the top( which is 2) ……therefore V= 2*4……ANSWER = 8. hope this helps