Question

balance the following equations....

1. 2mg + o₂ ---------> ______ mgo
2. p₄o₁₀ + ______ h₂o ---------> 4h₃po₄
3. 2nh₃ ---------> n₂ + ____ h₂
4. 2kclo₃ ---------> __ kcl + __ o₂

Explanation:

Step1: Balance equation 1 (Mg and O)

Left: 2 Mg, 2 O. Right: 1 Mg, 1 O. To balance Mg, need 2 MgO (so Mg: 2, O: 2). So coefficient is 2.

Step2: Balance equation 2 (P, O, H)

Left: 4 P, 10 O (from \(P_4O_{10}\)), 2 H (from \(H_2O\)). Right: 4 P, 16 O (4\(H_3PO_4\): 4×4=16), 12 H (4×3=12). For H: \(H_2O\) needs 6 (6×2=12 H). Check O: \(P_4O_{10}\) (10 O) + 6\(H_2O\) (6 O) = 16 O (matches right). So coefficient is 6.

Step3: Balance equation 3 (N and H)

Left: 2 N, 6 H (2\(NH_3\)). Right: 2 N (from \(N_2\)), need 3 \(H_2\) (3×2=6 H). So coefficient is 3.

Step4: Balance equation 4 (K, Cl, O)

Left: 2 K, 2 Cl, 6 O (2\(KClO_3\)). Right: KCl (K:1, Cl:1), \(O_2\) (O:2). For K and Cl: need 2 KCl (2 K, 2 Cl). For O: 6 O / 2 = 3 \(O_2\). So KCl coefficient 2, \(O_2\) coefficient 3.

Answer:

1. 2
2. 6
3. 3
4. 2; 3