Question

$50$ gram of calcium carbonate was completely burnt in air. What is the weight (in grams) of the residue?

• A. 28
• B. 2.8
• C. 46
• D. 4.8

Answer 1

Answer: (A)

$CaC{O}_3⟶CaO\text{ (residue) }+C{O}_2\uparrow$
$100\text{ gram }⟶56\text{ gram }$
$50$ gram gives $56/2=28$ gram.