Elements, Compounds and Mixtures Flashcards
How many types of atom are in an element?
1
How many types of atom are in a compound?
2 or more
Are elements in compounds chemically combined?
Yes
Are elements in mixtures chemically combined?
No
What do chemical formulae show?
They are used to describe compounds - e.g. H2O is two hydrogen atoms and one oxygen atom which have been chemically combined.
How many elements or compounds is a pure substance made of?
1
Do compounds have fixed melting and boiling points?
Yes
Do mixtures have fixed melting and boiling points?
No
Which of the two, compound or mixture, can be separated by physical means?
Mixture
Describe a solution:
A solution is made when a soluble solid dissolves in a liquid.
What is the liquid part of a solution called?
Solvent
What is the solid part of a solution called?
Solute
What is the other name for evaporation?
Crystallisation
Describe evaporation:
The solvent will evaporate leaving behind the solute.
What is group 1 of the periodic table commonly known as?
The alkali metals
What are the properties of group 1 on the periodic table?
Very reactive, very soft, low melting point and low density.
Where do the transition metals sit on the periodic table?
The middle block
Are transition metals hard or soft?
Hard
Are transition metals good electronic conductors?
Yes
Do transition metals have a high or low melting and boiling point?
High
What is group 7 of the periodic table known as?
Halogens
Are halogens metallic or non-metal elements?
Non-metal
How many atoms form the simple molecules of halogens?
2
What is the name of the bond that links the atoms together in halogens?
A covalent bond