Question

State True or False.

$1$ mole of $Ca$ react with a half mole of oxygen gas to form 1 mole of $CaO$ which weighs $56$ gm.

• A. True
• B. False

Answer 1

The correct option is A True

The given statement is True.
1 mole of Ca react with half mole of oxygen gas to form 1 mole of CaO which weighs 56 gm.

$Ca+\frac{1}{2}{O}_2\to CaO$
The atomic masses of Ca and O are 40 gm/mol and 16 g/mol respectively.
The molar mass of CaO $40+16=56$ gm/mol.
Thus, mass of 1 mole of CaO will be 56 gm.