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 = \(\frac{RV}{RT}\)
n = \(\frac{6 \times 105}{0.082 \times 303}\)
n= 2.536mol