Which of the following chemical equations are balanced ?

Options

A. `AlCl_(3(aq)) + 3NH_(4)OH_((aq)) rarr Al(OH)_(3(s)) + 3NH_(4)Cl_((aq))`
B. `2AlCl_(3(aq)) + NH_(4)OH_((aq)) rarr 2Al(OH)_(3(s)) + NH_(4)Cl_((aq))`
C. `AlCl_(3(aq)) + 2NH_(4)OH_((aq)) rarr Al(OH)_(3(s)) + 2NH_(4)Cl_((aq))`
D. `3AlCl_(3(aq)) + 2NH_(4)OH_((aq)) rarr 3Al(OH)_(3(s)) + 2NH_(4)Cl_((aq))`

Answer

A

Explanation

`AlCl_(3(aq)) + 3NH_(4)OH_((aq)) rarr Al(OH)_(3(s)) + 3NH_(4)Cl_((aq))`
The chemical equations are balanced to satisfy the law of conservation of mass in chemical reactions. This can be verified by noting the number of atoms of each element on the reactant side as well as product side.