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 = RVRT n = 6×10.50.082×303 n= 2.536mol