How Fast Is Sound in Hydrogen?

Sound moves through hydrogen at 1,270 m/s — about 4× faster than in air. Hydrogen molecules are so light they vibrate faster, propagating pressure waves much more quickly. Inhaling helium raises voice pitch; hydrogen would do it more, but is dangerously explosive.

Sound moves fastest in solid materials — through diamond it travels at 12,000 m/s, nearly three times the speed it takes through bone.

• 4× faster than sound in air
• Hydrogen would raise voice more than helium