Q112P - Chemistry: Molecular Nature Of Matter And Change

Question

Give the name, empirical formula and molecular mass of the molecule depicted in the figure.

                                 

Step-by-Step Solution

Answer

Molecular Name - Disulfur dichloride

Empirical formula - SCI

Molecular Mass - 135.04 amu

Step 1: Defining Molecular mass, empirical formula and molecular name

Molecular mass is defined as the sum of atomic masses of atoms that are all present in the molecule. 

The chemical elements when divided by the greatest common factor give empirical formula.

The molecular name gives the identification of the composition of chemical elements present in the molecule.

Step 2:Name, molecular formula and molecular mass of structure given

Two sulfur atoms are present as central atoms and two chlorine atoms are present as terminal atoms.

This is a covalent compound, so the name is based on the number of atoms using prefixes.

The second element or the terminal atom changes its ending to “-ide”.

The molecular name is disulfur dichloride.

For the empirical formula, a subscript is divided by the greatest common factor .

${\mathbf{S}}_{\mathbf{2}}{\mathbf{CI}}_{\mathbf{2}}\mathbf{\to }{\mathbf{S}}_{\frac{\mathbf{2}}{\mathbf{2}}}{\mathbf{CI}}_{\frac{\mathbf{2}}{\mathbf{2}}}\mathbf{\to }\mathbf{SCI}$

The atomic mass of the elements present,

S = 32.07u, CI = 35.45u

Molecular mass

$\mathbf{=}\mathbf{2}\mathbf{\times }\mathbf{32}\mathbf{.}\mathbf{07}\mathbf{+}\mathbf{2}\mathbf{\times }\mathbf{35}\mathbf{.}\mathbf{45}$

Hence, Molecular Mass. $\mathbf{135}\mathbf{.}\mathbf{04}\mathbf{ }\mathbf{amu}$