Consider the following reaction for the preparation of chlorine gas in the laboratory by treating manganese dioxide with Hydrogen Chloriode.

Manganese ions (Mn2+) present in water can be removed by oxidation with chlorine dioxide (ClO2) asshown in the balanced redox reaction below.Mn2+ (aq) + 2ClO2 (aq) + 2H2O (l) ⇌ MnO2 (s) + 2ClO2– (aq) + 4H+ (aq)The reaction is an overall second order reaction with the following rate law:Rate = k[Mn2+][ClO2], where k = 1 x 104 units at pH 7 and 25°C[Mn2+] and [ClO2] are in the units of concentration mol/L.(a) What is the units of the rate constant, k? (1 point)(b) Describe how (i) the reaction rate and (ii) rate constant, k, would change when the concentration ofchlorine dioxide is increased to twice the initial amount (with all other factors remaining the same).(2 points)Page 3 of 3RestrictedOzone is another chemical that can be used to react with manganese in water:Mn2+ (aq) + O3 (g) + 2H2O (l) ⇌ MnO2 (s) + O2 (g) + 2H+ (aq)(c) Based on the reaction equilibrium, should the reaction be carried out at low or high pH for theeffective removal of Mn2+ in water? Briefly explain why. (2 points)(d) Refer the table of Standard Reduction Potential given. Based on the Eo values, name two chlorinecontaining compounds that can be used to react with Mn2+ present in water. (2 points)Reduction Half-Reaction Eo (V)MnO4− (aq) + 8H+ (aq) + 5e− ⇌ Mn2+ (aq) + 4H2O (l) +1.49MnO2 (s) + 4H+ (aq) + 2e−⇌ Mn2+ (aq) + 2H2O (l) +1.21HOCl (aq) + H+ (aq) + e− ⇌ Cl2 (g) + H2O (l) +1.63ClO3− (aq) + 6H+ (aq) + 5e− ⇌ ½Cl2 (g) + 3H2O (l) +1.47ClO4− (aq) + 2H+ (aq) + 2e− ⇌ ClO3− (aq) + H2O (l) +1.19Hg2Cl2 (s) + 2e− ⇌ 2Hg (l) +2 Cl− (aq) +0.27O3 (g) + H2O (l) + 2e− ⇌ O2 (g) +2OH− (aq) +1.24(e) In practice, one of the comparts in Part (d) does not removed manganese (Mn) from watereffectively. Which compound is it and why is it ineffective in the removal of manganese fromwater? (2 points)(f) Mn2+ is reacted to form MnO2 in the reaction shown above. Name one method in which MnO2 canbe removed from water. (1 point)

The following reaction takes place when manganese dioxide ( ) is treated with hydrochloric acid ( ).  Let's think about what is being oxidized and what is being reduced.Choose the correct statement from the following.Choose 2 answers:Choose 2 answers:(Choice A)     is reduced by losing oxygen.A  is reduced by losing oxygen.(Choice B)     is oxidised by losing oxygen.B  is oxidised by losing oxygen.(Choice C)     is reduced by gaining hydrogen.C  is reduced by gaining hydrogen.(Choice D)     is oxidised by losing hydrogen.D  is oxidised by losing hydrogen.

. Which word equation correctly describes the following reaction?Sodium metal reacts with chlorine gas to form sodium chloride.

Cl2 + 2KBr → 2KCl + Br2The chlorine replaces the bromine in a compound with . This is an example of a reaction.

Hydrogen chloride gas is prepared in the laboratory using conc. H2SO4 and NaCl. Answer the questions that follow based on this reaction.(i) Give the balanced chemical equation for the reaction with suitable condition[s] if any.