pure substances, mixtures and separations Flashcards
1
Q
what is a pure substance
A
a pure substance is composed of a single type of material only
2
Q
what are general characteristics
A
- its composition is fixed and constant
- its properties are fixed and constant eg melting point, boiling point and density
- the component parts cannot be separated by any physical process
3
Q
how do you know if a substance is pure?
A
if its melting point will be high and boiling point low. However, if there are impurities, the melting point is low and boiling point is high
4
Q
what is an element
A
an element is a pure substance that cannot be broken down into simpler substances by ordinary processes or chemical processes.
5
Q
what is an atom
A
an atom is the smallest particle of any element
6
Q
learn the physical properties of metals and non metals
A
check text
