How many grams of residue are obtained by heating 2.76 g of silver carbonate (Ag₂CO₃)?

Given:

• Ag = 108 g mol^-1
• C = 12 g mol^-1
• O = 16 g mol^-1

Silver carbonate decomposes on heating according to:

Ag₂CO₃ → 2Ag + CO₂ + 1/2 O₂

First calculate the molar mass:

Ag₂CO₃

= 2(108) + 12 + 3(16)

= 276 g mol^-1

Thus:

276 g Ag₂CO₃ gives 216 g Ag

For 2.76 g:

Residue = (216 × 2.76)/276

= 2.16 g

The residue is metallic silver because gaseous carbon dioxide and oxygen escape during decomposition. Thermal decomposition reactions are frequently used in metallurgy and analytical chemistry.

Residue Obtained = 2.16 g