Question

How to "balance" chemical equations in easy steps,from the chapter chemical and chemical reactions(any equation would do) Class 7

Answer 1

BALANCED EQUATION must contain:
i) equal no of atoms of each element
ii) on either side of the arrow of the equation

A Unbalanced Equation:
HgO              ----------->          Hg + O₂
No. of atoms:
Hg=1, O=1 (left side)                          Hg=1, O=2 (right side)

1. Balance the oxygen atoms:
2HgO         ---------------->        Hg + O₂
No. of atoms now are:
Hg=2, O=2 (left side)                            Hg=1, O=2 (right side)

2. Balance the mercury atoms:
2HgO          ----------------->       2Hg + O₂
No. of atoms now are:
Hg=2, O=2  (left side)                           Hg=2, O=2 (right side)

Hence, the equation is balanced.
2HgO  ----------------->  2Hg + O₂