C1: Fundamental Ideas (1) Flashcards
Diffusion
The automatic mixing of liquids and gases as a result of the random motion of their particles
What sort of particles diffuse the quickest?
Small, light ones.
Does diffusion take place faster in a liquid or a gas?
Gas, move around faster, more chance of a collision.
Elements
Substances made up of only one type of atom.
Compound
A substance made out of two or more elements chemically bonded together.
Mixture
When substances are mixed together and intermingle but do not react.
A mixture is not a pure substance.
Atomic no.
No. of protons.
BOTTOM NUMBER
Atomic Mass no.
No. of protons plus neutrons.
TOP NUMBER
No. of Protons =
No. of electrons.
What does the number of electrons on the outer shell of an element tell us?
What group it is in, and how it reacts.
Why does the relative atomic mass only count protons and neutrons?
Because electrons weigh 1/2000 of what protons and neutrons weigh, so are generally discounted.
Isotopes
Atoms of the same element with different numbers of neutrons.
