key terms Flashcards
What is an atom
Smallest piece of an element
What is an element
Substance made of 1 type of atom. Listed on the Periodic Table
What is a compound
Substance made of 2 or more elements chemically joined
What is meant by pure
Substance made of 1 type of particle
What is meant by a mixture
Two or more different particles not chemically joined in a space e.g. salt water, air
What is meant by a molecule
Particle made of more than one atom chemically joined. The elements are usually non-metals. There are weak forces of attraction between molecules.
What is meant by a particle
General name for any small piece of matter. Can be atoms or molecules (or ions).
What is the periodic table
List of all known elements with their symbols
What is meant by a formula
How chemists show the combination of elements in a particle e.g. CuSO4 or Na
How do the properties of a compound relate to the elements they are made from
There is no relationship – compounds can have very different properties from the elements they are made from
What is between the shells of electrons
Nothing
How do we calculate the mass number of an atom
Number of protons + number of electrons
