first is to calculate the mass of required for the 0.50 M ammonium carbonate. assuming ammonium carbonate is 100 % pure
m = 0.5 L ( 0.50 mol ammonium carbonate / L) ( 96.09 g ammonium carbonate/ mol ammonium carbonate)
m = 24.0225 g ammonium carbonate
1. weigh 24.0225 g ammonium carbonate
2. place it in a 500-ml volumetric flask
3. add water to volumetric flask up to the line.
4. placed the cap and then shake properly.