Answer :
P = 2.8 atm, V = 750 mL = 750/1000 L = 0.75L, n = ?, T = 53.6 + 273 = 326.6 K, R = 0.08205 Latm/Kmol
PV = nRT
n = PV/RT
n = (2.8*0.75) / (0.08205*326.6)
n ≈ 0.078 mol
PV = nRT
n = PV/RT
n = (2.8*0.75) / (0.08205*326.6)
n ≈ 0.078 mol