Question

Write the formula by criss-cross method of Magnesium oxalate.

Answer 1

The symbol of magnesium is ‘Mg’, having a valency of 2⁺.

The formula of Oxalate is ‘C₂O₄’ with valency 2^-.

Step 1 –

Write the formula of magnesium oxalate:

Symbol Valency

Magnesium Mg 2⁺

Oxalate C₂O₄ 2^-

Step 2 –

Write each symbol with its valency:

Mg²⁺ C₂O₄^2-

Step 3 –

Interchanging the valences:

$$\begin{gathered} \mathrm{Mg}{\mathrm{C}}_2{\mathrm{O}}_{4_{}} \\ \searrow \swarrow \\ {2}^{+}{2}^{-} \end{gathered}$$

The formula of the compound Magnesium oxalate is MgC₂O₄.