Question

Balance the following equations: (a) \(\mathrm{CaC}_{2}(s)+\mathrm{H}_{2} \mathrm{O}(l) \longrightarrow \mathrm{Ca}(\mathrm{OH})_{2}(s)+\mathrm{C}_{2} \mathrm{H}_{2}(g)\) (b) \(\left(\mathrm{NH}_{4}\right)_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}(s) \longrightarrow \mathrm{Cr}_{2} \mathrm{O}_{3}(s)+\mathrm{N}_{2}(g)+\mathrm{H}_{2} \mathrm{O}(g)\) (c) \(\mathrm{CH}_{3} \mathrm{NH}_{2}(g)+\mathrm{O}_{2}(g) \longrightarrow \mathrm{CO}_{2}(g)+\mathrm{N}_{2}(g)+\mathrm{H}_{2} \mathrm{O}(g)\)

Short answer

Question: Balance the following chemical equations: (a) CaC₂(s) + H₂O(l) → Ca(OH)₂(s) + C₂H₂(g) (b) (NH₄)₂Cr₂O₇(s) → Cr₂O₃(s) + N₂(g) + H₂O(g) (c) CH₃NH₂(g) + O₂(g) → CO₂(g) + N₂(g) + H₂O(g) Answer: (a) CaC₂(s) + 2H₂O(l) → Ca(OH)₂(s) + C₂H₂(g) (b) (NH₄)₂Cr₂O₇(s) → Cr₂O₃(s) + N₂(g) + 4H₂O(g) (c) 2CH₃NH₂(g) + 3O₂(g) → 2CO₂(g) + N₂(g) + 4H₂O(g)

Step-by-step solution

List the number of atoms on each side

On the left side, we have 1 Ca, 2 C, and 2 H atoms. On the right side, we have 1 Ca, 2 O, 1 C, and 2 H atoms.

Adjust the coefficients

To balance the equation, adjust the coefficients: \(\mathrm{CaC}_{2}(s)+2\mathrm{H}_{2} \mathrm{O}(l) \longrightarrow \mathrm{Ca}(\mathrm{OH})_{2}(s)+\mathrm{C}_{2} \mathrm{H}_{2}(g)\) (b) $\left(\mathrm{NH}_{4}\right)_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}(s) \longrightarrow \mathrm{Cr}_{2} \mathrm{O}_{3}(s)+\mathrm{N}_{2}(g)+\mathrm{H}_{2} \mathrm{O}(g)$

List the number of atoms on each side

On the left side, we have 2 N, 8 H, 2 Cr, and 7 O atoms. On the right side, we have 2 Cr, 3 O, 2 N, and 2 H atoms.

Adjust the coefficients

To balance the equation, adjust the coefficients: $\left(\mathrm{NH}_{4}\right)_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}(s) \longrightarrow \mathrm{Cr}_{2} \mathrm{O}_{3}(s)+\mathrm{N}_{2}(g)+4\mathrm{H}_{2} \mathrm{O}(g)$ (c) $\mathrm{CH}_{3} \mathrm{NH}_{2}(g)+\mathrm{O}_{2}(g) \longrightarrow \mathrm{CO}_{2}(g)+\mathrm{N}_{2}(g)+\mathrm{H}_{2} \mathrm{O}(g)$

List the number of atoms on each side

On the left side, we have 1 C, 3 H, 1 N, and 2 O atoms. On the right side, we have 1 C, 1 N, 1 H, and 3 O atoms.

Adjust the coefficients

To balance the equation, adjust the coefficients: \(2\mathrm{CH}_{3} \mathrm{NH}_{2}(g)+3\mathrm{O}_{2}(g) \longrightarrow 2\mathrm{CO}_{2}(g)+\mathrm{N}_{2}(g)+4\mathrm{H}_{2} \mathrm{O}(g)\)