What is the molar mass of the compound represented by the following structural formula?

Elements $A$ and $B$ form two compounds $B_2A_3$ and $B_2A$. $0.05$ moles of $B_2A_3$ weigh $9.0 \ g$ and $0.10$ mole of $B_2A$ weigh $10 \ g$. The atomic weights of $A$ and $B$ are:

The atomic mass of an element is $27$. If its valency is $3$,what is the vapor density of its volatile chloride?

An element of mass $A_1 \, g$ gives a chloride of mass $A_2 \, g$. Calculate its equivalent mass.

Assertion : Equivalent weight of a base $= \frac{\text{Molecular weight}}{\text{Acidity}}$
Reason : Acidity is the number of replaceable hydrogen atoms in one molecule of the base.

The equivalent weight of $H_3PO_4$ in the following reaction is: $H_3PO_4 + Ca(OH)_2 \to CaHPO_4 + 2H_2O$