Calculate the amount in moles of a gas which occupies 10.5 dm³ at 6 atm and 30°C [R = 082 atmdm³k-¹ mol]

A. 2.536
B. 1.623
C. 4.736
D. 0.394

Correct Answer:

Option A – 2.536

Explanation

For an ideal gas PV = nRT

Amount in moles = n

Volume v = 10.5dm³

Pressure P = 6atm

Temperature T = 30°C + 273 = 303k

R, Gas constant = 0.082 atmdm³k-¹ mol

Recall from ideal gas equation

pv = nRT

n = RV/RT

n = (6×105)/(0.082×303)

n= 2.536mol