Question

Write the chemical formula of the following compound in a step-by-step manner –

Calcium hydroxide

Answer 1

Write the formula of

Calcium hydroxide	Symbol	Valency
Calcium	\[\ce{Ca}\]	\[\ce2^+\]
Hydroxide	\[\ce{OH}\]	\[\ce1^-\]

Step I – Write each symbol with its valency.
Positive ion is written first
\[\ce{Ca}^{2+}\]  \[\ce{[OH]}^{1-}\]
Step II – Interchange the valencies and ignoring the positive and negative signs.

The Formula is \[\ce{Ca[OH]2}\]