A substance that cannot split up into any other substances.
What is an element?
100
A shorthand way of describing an atom, an ion or a molecule.
What is a chemical formula?
100
H2O
What is waters chemical formula?
100
Deoxyribonucleic acid (A long double-spiral molecule that is found in every living cell)
What is DNA?
200
The smallest particle of a substance that can exist on its own
What is a molecule?
200
112
How many elements have been discovered?
200
Substances that contain several chemical elements or compounds mixed together but not chemically joined
What is a mixture?
200
Ice
What is freezed water?
200
Thick liquids that won't mix with water
What are oils?
300
A atom that has lost one or a few electrons
What is an ion?
300
Hydrogen*
What is the lightest element?
300
78.9% nitrogen, 20.95% oxygen. Also traces of argon (0.93%), carbon dioxide (0.03), helium (0.0005%), neon (0.018%), krypton (0.001%), xenon (0.0001% and radon.
What is pure air made of?
300
The percentage of water in your body
What is three quarters
300
Animals breath out croon as carbon dioxide. Plants take in carbon dioxide from the air and convert it into carbohydrates. When animals eat plants, they take in the carbon again.
What is the carbon cycle?
400
Quarks and leptons*
What is the smallest particle of all?
400
Hahnium*
What is the heaviest element?
400
Oxygen, carbon dioxide, nitrogen and different salts dissolved in it.
What is the sea made of?
400
Electricity generated turbines turned by falling water
What is hydroelectric power (HEP) ?
400
Carbon Atoms linked together like the links of a chain to form a very long thin molecule.
What is a carbon chain?
500
Very tiny electrically charged particles that whizz around inside an atom
What are electrons?
500
The weight of one whole atom of a substance.
What is atomic mass?
500
A chemical reaction caused when an electric current is passed through a substance,The......