Answer:
CheckedStep-by-step explanation:
Helium is an inert gas; it is the least reactive element in the noble gas family. In other words, Helium is completely inert, it does not react with any other element.
The pressure exerted by the non reactive gases can be calculated by Dalton's law of partial pressure according to which:-
At constant volume and temperature the pressure of any two or more non reactive gases is the sum of their partial pressures.
Hence, pressure of Heliox mixture will be
PT = P He + PO2
=0.75 + 0.35
= 1.10 atm