Chapter 03 Atoms and Molecules Questions-03
Questions
1. Write down the formulae of
(i) sodium oxide
(ii) aluminium chloride
(iii) sodium suphide
(iv) magnesium hydroxide
Show Answer
Answer
(i)
(ii)
(iii)
(iv)
2. Write down the names of compounds represented by the following formulae:
(i)
(ii)
(iii)
(iv)
(v)
Show Answer
Answer
(i) Aluminium sulphate
(ii) Calcium chloride
(iii) Potassium sulphate
(iv) Potassium nitrate
(v) Calcium carbonate
3. What is meant by the term chemical formula?
Show Answer
Answer
Chemical formula of a compound (or element) is the symbolic representation of its composition. It represents
(i) The number and kind of atoms present per molecule of the compound,
(ii) One mole of the compound,
(iii) Molar mass of the compound.
4. How many atoms are present in a
(i)
(ii)
Show Answer
Answer
(i) 2 atom of hydrogen +1 atom of sulphur
(ii) 1 atom of phosphorus +4 atoms of oxygen
