Using the activity series (Table 4.5), write balanced chemical equations for the following reactions. If no reaction occurs, write NR. (d) chromium metal is immersed in an aqueous solution of cobalt(II) chloride

Verified step by step guidance

1. Identify the reactants: chromium metal (Cr) and cobalt(II) chloride (CoCl_2).
2. Write the unbalanced chemical equation: Cr(s) + CoCl_2(aq) -> Co(s) + CrCl_2(aq).
3. Consult the activity series to determine if a reaction will occur. Chromium must be more reactive than cobalt for the reaction to proceed.
4. If chromium is more reactive than cobalt, balance the chemical equation by ensuring the number of atoms of each element is the same on both sides.
5. If chromium is not more reactive than cobalt, write 'NR' to indicate no reaction occurs.

Key Concepts

Activity Series

The activity series is a list of metals ranked by their ability to displace other metals from solutions of their ions. Metals higher in the series can displace those lower from their compounds. Understanding this series is crucial for predicting whether a reaction will occur when a metal is placed in a solution containing another metal's ions.

Redox Reactions

Redox (reduction-oxidation) reactions involve the transfer of electrons between substances, leading to changes in oxidation states. In the context of metal displacement reactions, the more reactive metal will be oxidized (lose electrons), while the less reactive metal ion will be reduced (gain electrons). Recognizing these changes is essential for writing balanced chemical equations.

Balanced Chemical Equations

A balanced chemical equation represents a chemical reaction with equal numbers of each type of atom on both sides of the equation. Balancing ensures the law of conservation of mass is upheld. In displacement reactions, it is important to correctly represent the reactants and products, including any ions in solution, to accurately depict the reaction that occurs or indicate if no reaction (NR) takes place.