Pure and impure substances Flashcards
1
Q
What is an elememt?
A
A pure substance that cannot be broken down into simpler instances by chemical or physical means.
2
Q
What is a compound?
A
A pure substance that can be broken down into simpler substances by chemical means.
3
Q
What are mixtures?
A
Two or more elements and/or compounds NOT chemically combined. Can be seperated by physical means.
4
Q
Elements and compounds are ….. substances.
A
Pure
5
Q
Mixtures are ….. substances.
A
Impure
6
Q
Name the five ways of separating mixtures.
A
- hand sorting
- sieve/filter
- magnet (magnetic substances)
- evaporation
- distillation
7
Q
What are compounds made up of?
A
Two or more atoms of different elements.
8
Q
What is a chemical bond?
A
An electronic force of attraction between atoms.
9
Q
What are the three main types of chemical bonds?
A
- metallic bond: between metal atoms.
- covlent bond: between non-metals atoms.
- ionic bond: between metal and non-metals.
10
Q
When atoms combine to form a particular compound, they always do so in a …….. ……..
A
Constant ratio
