Formula and equations - 2.3 - (2) Flashcards
Page 16
1
Q
What are polyatomic ions?
A
ions that contain atoms of more than one element bonded / joined together
2
Q
What does an ionic compound contain?
A
a cation and an anion
3
Q
How can the formula be worked out?
A
from the charge on each ion
4
Q
Writing formulae from ions: The overall charge is zero so…
A
the ionic charges must balance
5
Q
Writing formulae from ions: Sum of positive charges = …
A
sum of negative charges
6
Q
What is the number of each ion present shown as?
A
a subscript after the ion
7
Q
The ionic charges are usually omitted…
A
in the completed formula
8
Q
When are brackets used?
A
if there is more than one polyatomic ion
