For each pair of reactants, will there be a reaction? Co(s) + HCl(aq) No reaction Fe(s) + CuSO4(aq) Cr(s) + Co(NO3)2(aq) No reaction Reaction Sn(s) + Mg(NO3)2(aq) No reaction
The Correct Answer and Explanation is:
To determine if a reaction will occur between the given pairs of reactants, we need to consider factors like reactivity series, the nature of the compounds, and the possibility of displacement reactions. Here’s the analysis for each pair:
- Co(s) + HCl(aq) – No reaction
In this case, cobalt (Co) is a metal, and hydrochloric acid (HCl) is an acid. However, cobalt is less reactive than hydrogen, meaning it cannot displace the hydrogen ions (H⁺) from the acid. For a displacement reaction to occur, the metal must be more reactive than the ion it displaces. Since cobalt is less reactive than hydrogen, no reaction occurs in this case. - Fe(s) + CuSO4(aq) – Reaction
Iron (Fe) is more reactive than copper (Cu) according to the reactivity series. When iron is placed in copper(II) sulfate (CuSO₄), a displacement reaction takes place. Iron displaces copper from the sulfate solution, forming iron(II) sulfate (FeSO₄) and copper metal. The reaction is as follows: Fe(s)+CuSO4(aq)→FeSO4(aq)+Cu(s)Fe(s) + CuSO₄(aq) \rightarrow FeSO₄(aq) + Cu(s)Fe(s)+CuSO4(aq)→FeSO4(aq)+Cu(s) This is a typical single displacement reaction. - Cr(s) + Co(NO3)2(aq) – No reaction
Chromium (Cr) is less reactive than cobalt (Co) in the reactivity series. Therefore, chromium cannot displace cobalt ions (Co²⁺) from cobalt nitrate (Co(NO₃)₂). No reaction will take place between chromium and cobalt nitrate. - Sn(s) + Mg(NO3)2(aq) – No reaction
Tin (Sn) is less reactive than magnesium (Mg). In this case, tin cannot displace magnesium from magnesium nitrate (Mg(NO₃)₂) because magnesium is higher on the reactivity series. Thus, no reaction will occur.
Summary
- Fe + CuSO₄: Reaction (displacement of copper by iron).
- Cr + Co(NO₃)₂: No reaction (chromium is less reactive than cobalt).
- Sn + Mg(NO₃)₂: No reaction (tin is less reactive than magnesium).
- Co + HCl: No reaction (cobalt is less reactive than hydrogen).
