Verified answer

the He is irrelevant for what you are trying to find. what you have is right. When the question says ideal gas it makes various assumptions and the end result is that all gasses are the same. If the question was a real gas question then you would need to use the He because you would need to use the vander wol attraction variables A and B but you dont need to worry about that for this problem.

T temperature to be measured on kelvin scale.. i.e. 19+273 ok and no of moles.. weight divided by molecular weight fee of R 2 b chosen accordin to the instruments used for pressur en volume.. if u use atm-l then the linked fee of R is 0.0821 if u use pascal-m^3 fee is 8.314 and for calculation of warmth or potential in energy, fee of R shud be approximated to 2