(N/A) To derive the molecular formula for Ammonium carbonate,we follow these steps:
$1$. Identify the ions and their respective charges:
- Ammonium ion: $NH_4^+$ (charge = $+1$)
- Carbonate ion: $CO_3^{2-}$ (charge = $-2$)
$2$. Write the symbols and their charges side-by-side:
- Symbol: $NH_4$ and $CO_3$
- Charge: $+1$ and $-2$
$3$. Use the criss-cross method to balance the charges:
- The charge of the Ammonium ion $(+1)$ becomes the subscript for the Carbonate ion.
- The charge of the Carbonate ion $(-2)$ becomes the subscript for the Ammonium ion.
$4$. Combine them to form the neutral compound:
- Since we need two Ammonium ions to balance one Carbonate ion,the formula is $(NH_4)_2CO_3$.