30. Helium gas is used in gas balloons instead of hydrogen gas because it is A.Lighter than hydrogen B.More abundant than hydrogen C.Non-combustible D.More stable
Answer: Option C Solution: Helium gas is lighter than air, therefore, a helium balloon rises, it is known as a noble gas and is therefore not reactive. Hydrogen is also lighter than air and even lighter than helium. However, Hydrogen is not used in balloons because it is highly explosive and flammable.
