Question

The formula, $CaC{O}_3$, quantitatively signifies that:

• A. one molecule of calcium carbonate
• B. one molecule of calcium carbonate is made up of one atom of calcium, one atom of carbon and three atoms of oxygen
• C. 100 parts by weight of calcium carbonate [At. wt. $Ca=40,C=12,O=16]$
• D. 40 parts by weight of calcium, 12 parts by weight of carbon and 48 parts by weight of oxygen

Answer 1

Answer: (A), (B), (C), (D)

The correct options are
A one molecule of calcium carbonate
B one molecule of calcium carbonate is made up of one atom of calcium, one atom of carbon and three atoms of oxygen
C 40 parts by weight of calcium, 12 parts by weight of carbon and 48 parts by weight of oxygen
D 100 parts by weight of calcium carbonate [At. wt. $Ca=40,C=12,O=16]$

The formula, $CaC{O}_3$, quantitatively signifies one molecule of calcium carbonate. From this it is clear that one atom of calcium, one atom of carbon and 3 atoms of oxygen combine to give calcium carbonate. Molecular weight of $CaC{O}_3$ is 100. Atomic mass of Ca (40) + atom mass of carbon $\left(12\right)+3\times$ atomic mass of oxygen (16).