Question

question 30
select the correct set of (unbalanced) products for the following reaction:
(nh₄)₂co₃ (aq) + cucl₂ (aq) →
○ cuco₃ (aq) + nh₄cl (aq)
○ cuco₃ (s) + nh₃(g) + hcl (g)
○ cu (s) + co₂ (g) + nh₃ (g) + cl₂ (g)
○ cuco₃ (s) + nh₄cl (aq)

Explanation:

Step1: Identify Reaction Type

The reaction is between \((NH_4)_2CO_3(aq)\) and \(CuCl_2(aq)\), which is a double - displacement reaction. In double - displacement reactions, the cations and anions of the two reactants switch places. The general form of a double - displacement reaction is \(AB + CD
ightarrow AD+CB\), where \(A\) and \(C\) are cations, and \(B\) and \(D\) are anions.

For \((NH_4)_2CO_3(aq)\) (where \(A = NH_4^+\), \(B = CO_3^{2 - }\)) and \(CuCl_2(aq)\) (where \(C = Cu^{2+}\), \(D = Cl^-\)):

The products should be formed by swapping the ions. So, \(NH_4^+\) combines with \(Cl^-\) and \(Cu^{2+}\) combines with \(CO_3^{2 - }\).

Step2: Determine Product Formulas

• The formula for the compound formed from \(Cu^{2+}\) and \(CO_3^{2 - }\) is \(CuCO_3\). Since carbonates of transition metals like copper (II) are generally insoluble in water, \(CuCO_3\) will be a solid (\(s\)).
• The formula for the compound formed from \(NH_4^+\) and \(Cl^-\) is \(NH_4Cl\). Ammonium chloride is soluble in water, so it will be in the aqueous (\(aq\)) state.

Now let's analyze each option:

• Option 1: \(CuCO_3(aq)+NH_4Cl(aq)\): \(CuCO_3\) is insoluble, so it should be a solid, not aqueous. Eliminate this option.
• Option 2: \(CuCO_3(s)+NH_3(g)+HCl(g)\): There is no redox reaction or reaction that would produce \(NH_3\) and \(HCl\) from this double - displacement reaction. Eliminate this option.
• Option 3: \(Cu(s)+CO_2(g)+NH_3(g)+Cl_2(g)\): There is no redox reaction to produce elemental copper or chlorine gas. Eliminate this option.
• Option 4: \(CuCO_3(s)+NH_4Cl(aq)\): This matches the products of the double - displacement reaction, with \(CuCO_3\) as a solid and \(NH_4Cl\) in aqueous solution.

Answer:

The correct option is the one with \(CuCO_3(s)+NH_4Cl(aq)\) (the fourth option in the given list of options).