Page 48 - Understanding NCERT Science 09

Example 2 : A low cost model for writing formulae: Take empty
blister packs of medicines. Cut them in groups,
according to the valency of the element, as shown in
the figure. Now, you can make formulae by fixing
one type of ion into other.

For example:

Na + SO 2- P0 3-
4 4

Formula for sodium sulphate:
2 sodium ions can be fixed on one sulphate ion.
Hence, the formula will be: Na SO
2 4
Do it yourself :
Now, write the formula of sodium phosphate.

ATOMS AND MOLECULES 37

Rationalised 2023-24