Which gem is made of pure carbon?
AnswerDiamond
Diamond is carbon atoms in a rigid crystal lattice.
Science · Facts & stats
Carbon facts & stats
7 fact-checked facts about carbon: the element, its forms and the carbon cycle, each with the reason behind it. 5 more are in today's round and join this page after it closes.
The basics
Pencil 'lead' is actually made mostly of what?
AnswerGraphite
Pencil cores are graphite mixed with clay.
Going deeper
What is carbon's atomic number?
Answer6
Carbon has six protons; 12 is the mass number of its most common isotope.
Carbon-14 dating is used to estimate the age of what?
AnswerOnce-living organic material
It works on organic remains up to roughly 50,000 years old.
What is graphene?
AnswerA single layer of carbon atoms in a honeycomb lattice
Graphene is one atom thick and very strong.
Expert level
What is the half-life of carbon-14?
AnswerAbout 5,730 years
Half of any carbon-14 decays roughly every 5,730 years.
The ball-shaped C60 molecule is named after which architect?
AnswerBuckminster Fuller
Buckminsterfullerene echoes Fuller's geodesic domes.
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