We are given
n = 87.3 moles He
no = 52.0 moles
Po = 9.63 atm
Using the relationship between Pressure and number of moles
Po/no = P/n
Substituting
9.63 atm / 52.0 mol = P / 87.3 mol
Solve for P<span />
The answer is a since its a physical to chemical change
Vectors include magnitude & direction so the third option is the correct answer :)
