Please help me with these gas problems (Grade 11)

1a) The kelvin temp of a 3L sample of oxygen gas is tripled while the pressure is help constant. What is the new volume of oxygen?

b) Air trapped in a syringe at 100KPA of pressure has its volume decreased to 1/8 of its initial volume. If the temp is constant, the pressure in the syringe is?..

Question

Please help me with these gas problems (Grade 11)

1a) The kelvin temp of a 3L sample of oxygen gas is tripled while the pressure is help constant. What is the new volume of oxygen?

b) Air trapped in a syringe at 100KPA of pressure has its volume decreased to 1/8 of its initial volume. If the temp is constant, the pressure in the syringe is?..

anonymous · Answer

ok so first start by writing ideal gas equation:
pV=nRT
now you have same amount of oxygen before and after so you can write next:
n1=n2
and as n=pV/RT
and R is constant so it would cross itself out you are left with:
p1V1/T1 = p2V2/T2
so you have that pressure is constant so you can cross it out too and you are left with:
V1/T1=V2/T2
hope you get it...

pottersheep · Answer

oo got the first one thanks! now ill work on the second one

anonymous · Answer

oh great, somebody who is willing to use head! glad to help

pottersheep · Answer

Yayy i got the second one too now :)

anonymous · Answer

congrats!

pottersheep · Answer

thanks! :)

anonymous · Answer

not a problem.