Question

50% of by mass of a 2.2 moles mixture of He and Ar gasses is He. Calculate the mole number of He in the mixture?

Answer 1

Answer:8g

Explanation:He=4

Ar=40

n(mol)(Total)=nHe + nAr

2.2=m/M(He) + mM(Ar)

2.2= x/4 + x/40

2.2=0.25X +0.025X

2.2=0.275X

X=2.2/0.275-->8g