How many moles of H2 would be contained in 4.0 L of the gas at 202.6 kPa and 127°C?
A. 89.6 mol
B. 6.38 mol
C. 0.24 mol
D. 0.77 mol

Question

How many moles of H2 would be contained in 4.0 L of the gas at 202.6 kPa and 127°C?
  A. 89.6 mol 	
  B. 6.38 mol 	
  C. 0.24 mol 	
  D. 0.77 mol

anonymous · Answer

@JFraser  i  think its (B)

jfraser · Answer

use the ideal gas law$$P*V = n*R*T$$just be sure to convert your temp to kelvin, just like before

jfraser · Answer

that's not what i get, check your values and make sure you're using the proper value for R based on the units of pressure

anonymous · Answer

i got (D)

jfraser · Answer

if you got D, then you forgot to convert the temperature to kelvin

anonymous · Answer

oh. then let me redo it

anonymous · Answer

A

jfraser · Answer

it's not A, either. let me show you the setup

jfraser · Answer

starting with$$P*V = n*R*T$$is rearranged to solve for $n$$$n = \frac{P*V}{R*T}$$

anonymous · Answer

c?

anonymous · Answer

or was i right with b?

jfraser · Answer

$$n = \frac{(202.6kPa)*(2.0L)}{(8.31\frac{kPa*L}{mol*K})*(400K)}$$

jfraser · Answer

the answer is C)

jfraser · Answer

when you work with gases, the temp has to be in K