A 2.50 L flask was used to collect a 5.65 g sample of propane gas, C3H8. After the sample was collected, the gas pressure was found to be 741 mmHg. What was the temperature of the propane in the flask.

P= 741 mmHg(1 atm/760 mmHg)= .975 atm
V= 2.50 L
n= 5.65 g C3H8 (1 mol/44 g)= .128 mol
R= 0.0821
T= ?

.975(2.50)= .128(0.0821)(T)
2.4375 = .0151(T)

ANSWER:
161.4238 = T

Is this correct

3 answers

P= 741 mmHg(1 atm/760 mmHg)= .975 atm
V= 2.50 L
n= 5.65 g C3H8 (1 mol/44 g)= .128 mol
R= 0.0821
T= ?

.975(2.50)= .128(0.0821)(T)
2.4375 = .0151(T) The mistake is here. 0.128 x 0.0821 = 0.0105

I have an answer of about 232.
Okay I see where I went wrong
hydrogen cynaride is a highly poisonous, volatile liquid. it can be prepared by the reaction CH4(g)+ NH3(g)--> HCN(g) + 3H2(g). what is the heat of the reaction at constant pressure? use the following thermochemical equations: N2(g)+3H2(g)-->2NH3(g)delta H=-91.8 Kj, C(graphite)+2H2(g)-->CH4(g) delta H=-74.9 Kj, H2(g)+2C(graphite)+N2(g)-->2HCN(g) delta H= 270.3 Kj