Why do helium balloons float?
AnswerHelium is less dense than air
Lighter-than-air helium gives balloons lift.
Science · Facts & stats
Helium facts & stats
7 fact-checked facts about helium and the science of the noble gases, each with the reason behind it. 5 more are in today's round and join this page after it closes.
The basics
What is helium's chemical symbol?
AnswerHe
He is helium; H is hydrogen.
Going deeper
The name helium comes from the Greek word for what?
AnswerThe Sun
Helios is Greek for Sun.
Helium ranks where in abundance among elements in the universe?
AnswerSecond
Only hydrogen is more abundant.
Liquid helium is used to cool what in hospitals?
AnswerMRI magnets
It keeps MRI superconducting magnets extremely cold.
Expert level
At about what temperature does helium boil?
Answer4.2 kelvin
Helium boils near 4.2 K, about -269°C.
Which gas filled the Hindenburg airship?
AnswerHydrogen
The Hindenburg used flammable hydrogen, not helium.
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