Question

The molecular mass of ${\text{CaCl}}_2$ is :

• A. 110u
• B. 112u
• C. 100u
• D. 111u

Answer 1

The correct option is A

110u

The atomic mass of calcium = 40 u.
The atomic mass of chlorine = 35.5 u.
The molecular mass of ${\text{CaCl}}_2$
=1 $\times$ Atomic mass of calcium + 2 $\times$ Atomic mass of chlorine
= $1\times 40+2\times 35.5$
= $111$ u.