Question

Classify each of the following solids as ionic, metallic and molecular: P$_4$, Ammonium phosphate, Brass, Tetraphosphorus decoxide (P$_4$O$_{10}$), Rb, I$_2$, LiBr

Hint:

Molecular solids are usually soft and volatile, ionic solids are hard and brittle with high melting points, and metallic solids conduct electricity due to free electrons.

Answer 1

Step 1: Understanding the classification.
Solids are broadly classified as: -
Ionic solids: Composed of cations and anions held by electrostatic forces.
-
Metallic solids: Composed of metal atoms with mobile electrons (metallic bonding).
-
Molecular solids: Composed of discrete molecules held by van der Waals forces or hydrogen bonds.
Step 2: Classify each given substance.
\begin{tabular}{|c|c|} \hline Substance &
Type of Solid
\hline P$_4$ & Molecular solid
\hline Ammonium phosphate & Ionic solid
\hline Brass & Metallic solid (alloy of Cu and Zn)
\hline Tetraphosphorus decoxide (P$_4$O$_{10}$) & Molecular solid
\hline Rb (Rubidium) & Metallic solid
\hline I$_2$ & Molecular solid (van der Waals forces)
\hline LiBr & Ionic solid
\hline \end{tabular} Conclusion:
- Ionic solids: Ammonium phosphate, LiBr
- Metallic solids: Brass, Rb
- Molecular solids: P$_4$, P$_4$O$_{10}$, I$_2$