Question

In the reaction between lead(II) nitrate and sodium chloride, what, if any, are the spectator ions

Answer 1

In the reaction between lead(II) nitrate and sodium chloride, the spectator ions are the sodium ions (Na+) and the nitrate ions (NO3-), which remain in the solution before and after the reaction.

Step-by-step explanation:

In the reaction between lead(II) nitrate and sodium chloride, the spectator ions are ions that do not participate in the formation of the precipitate. When aqueous solutions of lead(II) nitrate and sodium chloride are mixed, the products of the reaction are an aqueous solution of sodium nitrate and a solid precipitate of lead(II) chloride. The balanced chemical equation is:

Pb(NO3)2 (aq) + 2 NaCl (aq) → PbCl2 (s) + 2 NaNO3 (aq)

Using this equation, we can identify the spectator ions by looking at what stays in solution before and after the reaction's completion. In this case, the sodium ions (Na+) and nitrate ions (NO3−) do not change and remain in solution. Hence, they are the spectator ions. The net ionic equation, which leaves out the spectator ions, is:

Pb2+ (aq) + 2 Cl− (aq) → PbCl2 (s)

Answer 2

Step-by-step explanation:

Spectator ions are ions in a solution/reaction that do not take part in a chemical reaction (hence are called "spectator" ions). They can be identified when they are found both in the reactant and product sides.

The reaction between lead(II) nitrate, Pb(NO₃)₂ and sodium chloride, NaCl is illustrated below

Pb(NO₃)₂ + 2NaCl ⇒ PbCl₂ + 2NaNO₃

According to solubility rules, all the compounds above (with the exception of PbCl₂) are all soluble and would dissociate when involved in a reaction.

Hence, the ionic equation based on the description above will be

Pb²⁺ + 2NO₃⁻ + 2Na⁺ + 2Cl⁻ ⇒ PbCl₂ + 2Na⁺ + 2NO₃⁻

From the above ionic equation, it can be noted that both 2NO₃⁻ and 2Na⁺ are found on both the reactant and product side and are hence the spectator ions.