Answer
moles of each syringe = 4.957x10^-4 moles
Explanation
Given:
Pressure = 1.2 atm
Volume = 4.2 mL
Temperature = -149 C
Required: Moles of gas
Solution:
The equation to use is:-
pV = nRT
where p is the pressure = 1.2 atm
V is the volume = 4.2 mL = 0.0042 L
n is the moles (the unknown)
R is the constant = 0.0820 L.atm.K-1.mol-1
T is the temperature = - 149 C = 124 K
Now we can re-arrange the equation and solve n
n = pV/RT
n = (1.2 atm x 0.0042 L)/(0.0820 L.atm.K-1.mol-1 x 124 K)
n = 4.957x10^-4 moles
