Question

In the extraction of copper from copper glance, blister copper is formed by the evolution of a gas X. The shape of molecule of X is

• A. Angular
• B. Planar trigonal
• C. Tetrahedral
• D. Pyramidal

Hint:

To determine the shape of a molecule, first draw its Lewis structure to count the number of bond pairs and lone pairs around the central atom. Then, apply VSEPR theory: the arrangement of electron pairs determines the electron pair geometry, while the arrangement of atoms determines the molecular shape.

Answer 1

The Correct Option is A

Step 1: Identify the gas X.
Copper glance is $Cu_2S$. The gas evolved during the formation of blister copper is $SO_2$. Thus, X is $SO_2$. Step 2: Determine the Lewis structure of $SO_2$.
Sulfur has 6 valence electrons, and each oxygen has 6 valence electrons. Total valence electrons = $6 + 2 \times 6 = 18$. The Lewis structure involves resonance and a lone pair on the sulfur atom. Step 3: Apply VSEPR theory to predict the shape.
The central sulfur atom has 2 bond pairs (with two oxygen atoms) and 1 lone pair of electrons. The electron pair geometry is trigonal planar. The molecular geometry, considering only the atoms, is bent or angular. Thus, the shape of the $SO_2$ molecule is $ \boxed{Angular} $.