Answer :
Explanation:
Use the Ideal Gas Law
PV = n R T P = 97.8 kPa V=.124 liters n = ? #moles
T = temp in Kelvin = 18 + 273.15 = 291.15 K
R = gas constant =8.314462618 L kPa / (K mol)
Substitute in the given numbers and solve for 'n'
97.8 * .124 = n * 8.314462618 * 291.15
n = .005 moles