Question

Which law of chemical combination does an unbalanced chemical reaction violate?.Explain with example

Answer 1

Law of Conservation of Mass

• The balancing of chemical equations is based on the law of conservation of mass.
• The Law of conservation of mass states that mass can be neither created nor destroyed in a chemical reaction.
• The total mass of reactants is equal to the total mass of products.
• In a chemical change, the total mass is conserved, that is the mass before the reaction is equal to the mass after the reaction.
• For example:

$$\begin{gathered} 2{\mathrm{H}}_2\left(\mathrm{g}\right)+{\mathrm{O}}_2\left(\mathrm{g}\right)\to 2{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right) \\ \mathrm{Mass}\mathrm{before}\mathrm{reaction}=2\mathrm{x}2+32=36 \\ \mathrm{Mass}\mathrm{after}\mathrm{reaction}=2\mathrm{x}(2+16)=36 \\ \mathrm{Mass}\mathrm{before}\mathrm{reaction}=\mathrm{Mass}\mathrm{after}\mathrm{reaction} \end{gathered}$$

An unbalanced chemical reaction violates the law of conservation of mass.

• For example:

$$\begin{gathered} {\mathrm{H}}_2\left(\mathrm{g}\right)+{\mathrm{O}}_2\left(\mathrm{g}\right)\to {\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right) \\ \mathrm{Mass}\mathrm{before}\mathrm{reaction}=2+32=34 \\ \mathrm{Mass}\mathrm{after}\mathrm{reaction}=2+16=18 \\ \mathrm{Mass}\mathrm{before}\mathrm{reaction}\ne \mathrm{Mass}\mathrm{after}\mathrm{reaction} \end{gathered}$$