Question

Write a balanced equation for each of the following single-replacement reactions: (a) Nickel metal is put into a lead(II) acetate solution. (b) Lead metal is put into a nickel(II) acetate solution.

Short answer

(a) \( \text{Ni} + \text{Pb(C}_2\text{H}_3\text{O}_2\text{)}_2 \rightarrow \text{Ni(C}_2\text{H}_3\text{O}_2\text{)}_2 + \text{Pb} \). (b) No reaction.

Step-by-step solution

Identify Elements and Compounds

For both reactions, identify the elements and compounds involved. In reaction (a), we have nickel (Ni) and lead(II) acetate ( ext{Pb(C}_2 ext{H}_3 ext{O}_2 ext{)}_2) and in reaction (b), we have lead (Pb) and nickel(II) acetate ( ext{Ni(C}_2 ext{H}_3 ext{O}_2 ext{)}_2).

Write Unbalanced Equations

Using chemical formulas, write the unbalanced equations. For reaction (a): \[\text{Ni} + \text{Pb(C}_2\text{H}_3\text{O}_2\text{)}_2 \rightarrow \text{???} \] and for reaction (b): \[ \text{Pb} + \text{Ni(C}_2\text{H}_3\text{O}_2\text{)}_2 \rightarrow \text{???} \]

Determine Products

In single-replacement reactions, the more reactive metal will replace the less reactive metal. For reaction (a), nickel will replace lead forming nickel(II) acetate and solid lead: \[ \text{Ni} + \text{Pb(C}_2\text{H}_3\text{O}_2\text{)}_2 \rightarrow \text{Ni(C}_2\text{H}_3\text{O}_2\text{)}_2 + \text{Pb} \]. Similarly, for reaction (b), since lead is less reactive than nickel, no reaction occurs.

Balance the Equations

Ensure that the number of each type of atom on both sides of the equation is equal. Reaction (a) is already balanced: \[ \text{Ni} + \text{Pb(C}_2\text{H}_3\text{O}_2\text{)}_2 \rightarrow \text{Ni(C}_2\text{H}_3\text{O}_2\text{)}_2 + \text{Pb} \]. Reaction (b) has no reaction, so no balancing is needed.

Key concepts

Balancing Chemical Equations

Play a crucial role in ensuring that a chemical reaction adheres strictly to the Law of Conservation of Mass. When balancing equations, you need to ensure that the same number of each type of atom appears on both sides of the equation. This means we are neither losing nor gaining any atoms during the reaction.

To balance an equation, follow these straightforward steps:

• Identify all reactants and products in the chemical equation.
• Count the atoms for each element on both the reactant and product sides.
• Use coefficients to adjust the number of atoms, making sure not to change the chemical identity (subscripts) of the compounds.
• Repeat until all elements are balanced.

Balancing chemical equations is a bit like solving a puzzle with specific rules. Once you get the hang of it, you'll see how satisfying it is to get everything just right!

Chemical Reactivity

Refers to how easily a chemical substance undergoes a chemical reaction. Reactivity varies between different elements and compounds and is influenced by factors such as electron configuration and exterior electron shell.

In the context of single replacement reactions, a more reactive element can replace a less reactive element in a compound. Here's how you can determine the likelihood of such a replacement:

• Observe the activity series for metals, which ranks metals according to their reactivity.
• In general, metals higher up can replace metals lower down from their compounds.
• For example, in reaction (a), nickel replaces lead because nickel is more reactive.
Recognizing reactivity is key to predicting the outcomes of potential reactions, telling you exactly when and how elements will swap places in a single replacement scenario.

Metal Reactivity Series

A useful tool that ranks metals from most to least reactive. The series helps chemists predict and understand various chemical reactions.

• Highly reactive metals, like potassium and sodium, are towards the top.
• Less reactive metals, like gold and platinum, are towards the bottom.
• The more reactive a metal, the more likely it will displace a less reactive metal from a compound.

This ranking is essential when dealing with single replacement reactions. For instance, nickel is more reactive than lead, allowing nickel to replace lead in a compound. However, because lead is less reactive than nickel, it cannot replace nickel, as seen in the second reaction.

Understanding the Metal Reactivity Series helps predict which metals can successfully participate in single replacement reactions and which reactions will be feasible or not.