# Chemistry help!

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A sample of gas at a temperature of 37.0°C has a pressure of 725 torr and occupies a volume of 3.44 L.

a. Use Boyle’s law to calculate the new pressure if the temperature is held constant and the volume is increased to 6.54 L.

torr

b. Use Gay-Lussac’s law to calculate the new pressure if the volume is held constant and the temperature is decreased to 6.00°C.

torr

c. Use Charles’ law to calculate the new volume if the pressure is held constant and the temperature is increased to 210°C.

L

d. Use the combined gas law to calculate the new pressure if the temperature is decreased to 25.0°C and the volume is increased to 16.9 L.

torr

e. Use the ideal gas law to calculate the number of moles of gas that are present.

Moles

A= p1v1=p2v2
725(3.44)=?(6.54) = 381.45

B. p1t1=p2/t2
725(6.00)/37.0. = 117.567

C= v1t1=v2t2
3.44(210)/37.0= 19.524

D= p1v1t1=p2v2t2
725*3.44/37.0=?(16.9)/25.0 = 45.566

E..?

I keep getting b,c,d,e wrong but I don't know what I'm doing wrong

• Chemistry help! -

2 errors on B
1. should be p1/t1 = p2/t2
2. T must be in kelvin and you used C
(725/310) = (p2/279)

C.wrong formula.
v1/t1 = v2/t2
(3.44/310) = v2/210)
Ans is approx 2.3 L

d.formula is (p1v1/t1) = (p2v2/t2)
(725*3.44/310) = p2*16.9/298).
Ans is approx 142.

e. PV = nRT
725*3.44 = n*0.0821*310
Solve for n.