s. A gas mixture contains 50% helium and 50% methane by volume. What i

1.	s. A gas mixture contains 50% helium and 50% methane by volume. What is the percent by weight of methane in themixture?A) 19.97%. B) 20.05%C) 50%
Answer» since % volume is same.. so, % moles will also be same so, Let total sum of moles be 1 moles of He = 1/2 → mass = 1/2(4) = 2g moles of CH4 = 1/2 → mass = 1/2(16) = 8g now, % weight of methane = 8/(8+2)×100 = 800/10 = 80%

s. A gas mixture contains 50% helium and 50% methane by volume. What is the percent by weight of methane in themixture?A) 19.97%. B) 20.05%C) 50%

Answer»

since % volume is same.. so, % moles will also be same

so, Let total sum of moles be 1 moles of He = 1/2 → mass = 1/2*(4) = 2g moles of CH4 = 1/2 → mass = 1/2*(16) = 8g

now, % weight of methane = 8/(8+2)×100 = 800/10 = 80%