3 g of H2, 16 g of O2 and 7 g of N2 are introduced into a 22.4 L container at 0°C. What is the total pressure in atmospheres? Answer: 2.25...Please let me know steps :)

Question

anonymous · Answer

well certainly we must use ideal gas law

$$PV=nRT$$

anonymous · Answer

$$P=\frac{nRT}{V}$$we know the value of $V$ and $T$  right?

anonymous · Answer

Thanks for your reply. V and T are known. n is the number of moles of 3 substances. With "R" I tried 0.0821 or 62.4. But I can't figure out pressure :(

anonymous · Answer

ok let me work on it...

$$R=0.08206 \frac{lit.atm}{mol.K}$$we know that  $T=273.15 K$  and  $V=22.4$ and 

$$n=\frac{3}{2}+\frac{16}{32}+\frac{7}{28}=2.25 mol$$so $$P=\frac{2.25\times0.08206\times 273}{22.4}=2.25 atm$$

anonymous · Answer

do u know how i evaluate $n$ ?

anonymous · Answer

Yes. Thank you for taking your time to show the steps :)

anonymous · Answer

welcome...