What is the sum of the coefficients in the balanced equation for the reaction of Mn^{2+} with NaOH to form Mn(OH)_2?

• A. 4
• B. 3
• C. 5
• D. 6

Answer: (C)

Verified step by step guidance

1. Identify the reactants and products: Manganese ion (Mn^{2+}) reacts with sodium hydroxide (NaOH) to form manganese(II) hydroxide, Mn(OH)_2.
2. Write the unbalanced chemical equation: \(\mathrm{Mn^{2+} + NaOH \rightarrow Mn(OH)_2 + Na^{+}}\).
3. Balance the chemical equation by ensuring the number of atoms of each element and the charges are equal on both sides. Since Mn(OH)_2 contains 2 hydroxide ions, you will need 2 NaOH molecules: \(\mathrm{Mn^{2+} + 2\ NaOH \rightarrow Mn(OH)_2 + 2\ Na^{+}}\).
4. Check that the equation is balanced in terms of atoms and charge: 1 Mn, 2 OH groups, 2 Na atoms on both sides, and charges balanced (2+ on left and 2+ on right).
5. Sum the coefficients of all species in the balanced equation: coefficients are 1 (Mn^{2+}) + 2 (NaOH) + 1 (Mn(OH)_2) + 2 (Na^{+}), which you add together to find the total sum.