Q111P - Chemistry: Molecular Nature Of Matter And Change

Question

Give the formula, name and molecular mass of the following molecules

Step-by-Step Solution

Answer

a)   Formula - ${\mathbf{N}}_{\mathbf{2}}\mathbf{O}$ 

Molecular Name- Nitrous oxide.

Molecular Mass-$\mathbf{=}\mathbf{44}\mathbf{.}\mathbf{02}\mathbf{ }\mathbf{amu}$

b)   Formula-${\mathbf{C}}_{\mathbf{2}}{\mathbf{H}}_{\mathbf{6}}$

Molecular Name- Ethane

Molecular Mass-$\mathbf{=}\mathbf{30}\mathbf{.}\mathbf{06}\mathbf{ }\mathbf{amu}$ 

Step 1: Defining Molecular mass, 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 composition of the substance is given by the chemical formula.

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

Step 2:Name, molecular mass and formula of a

The molecule consists of nitrogen atoms and an oxygen atom.

The Molecular formula is given as${\mathbf{N}}_{\mathbf{2}}\mathbf{O}$ .

The compound is nitrous oxide or dinitrogen monoxide.

Molecular Mass is given by$\mathbf{2}\mathbf{\times }\mathbf{atomic}\mathbf{ }\mathbf{mass}\mathbf{ }\mathbf{of}\mathbf{ }\mathbf{N}\mathbf{+}\mathbf{atomic}\mathbf{ }\mathbf{mass}\mathbf{ }\mathbf{of}\mathbf{ }\mathbf{O}$

Molecular mass$\mathbf{=}\left(2\times 14\right)\mathbf{+}\left(1\times 16\right)$

Molecular Mass$\mathbf{=}\mathbf{44}\mathbf{.}\mathbf{02}\mathbf{ }\mathbf{amu}$.

Step 3: Name, molecular mass and formula of structure given in b

The molecule consists of carbon atoms and each carbon is attached tohydrogen atoms.

The molecular formula is given as ${\mathbf{C}}_{\mathbf{2}}{\mathbf{H}}_{\mathbf{6}}$.

The compound is ethane.

Molecular mass is given by$\mathbf{2}\mathbf{\times }\mathbf{atomic}\mathbf{ }\mathbf{mass}\mathbf{ }\mathbf{of}\mathbf{ }\mathbf{C}\mathbf{+}\mathbf{6}\mathbf{\times }\mathbf{atomic}\mathbf{ }\mathbf{mass}\mathbf{ }\mathbf{of}\mathbf{ }\mathbf{H}$

Molecular mass$\mathbf{=}\left(2\times 12.00\right)\mathbf{+}\left(6\times 1.01\right)$

Molecular Mass.$\mathbf{=}\mathbf{30}\mathbf{.}\mathbf{06}\mathbf{ }\mathbf{amu}$