Question

1- Select True or False: The oxidation number of iodine increases by 6 in the following reaction.
2MnO₄^– + I^– + H₂O → 2MnO₂ + IO₃^– + 2OH^–

True

False

2- Shown here is the balanced molecular equation that would occur between CaCl₂(aq) and Na₂CO₃(aq). Which of the following is the balanced net ionic equation?
Molecular equation: CaCl₂(aq) + Na₂CO₃(aq) → CaCO₃(s) + 2NaCl(aq)

None of the above

Net ionic equation: Ca²⁺(aq) + CO₃^2–(aq) → Ca²⁺⁽aq) + CO₃(aq)

Net ionic equation: Ca²⁺(aq) + 2 Cl^–(aq) → CaCO₃(s)

Net ionic equation: Ca²⁺(aq) + CO₃^2–(aq) → CaCO₃(s)

Net ionic equation: 2Na⁺(aq) + CO₃^2–(aq) → Na₂CO₃(s)

3-Identify the major ionic species present in an aqueous solution of C₁₂H₂₂O₁₁ (sucrose).

12 C^-, 22 H⁺, 11 O^-

no ions are present

C₁₂⁺, 22 H⁺, 11 O^2-

12 CH²⁺, 11 O^2-

12 C⁺, 22 H⁺, 11 O^2-

^{Only type the answer thank you}

Answer 1

1. TRUE

2MnO₄^– + I^– + H₂O → 2MnO₂ + IO₃^– + 2OH^– in this reaction left side the oxidation number of I^- is -1 and the right side oxidation number of iodine is +5 so total change is 6.

2.Ca²⁺(aq) + CO₃^2–(aq) → CaCO₃(s)

Explanation:The ionic equation requires you to break these compounds into their ions if they exist in solution.Calcium carbonate is insoluble whilst sodium chloride is not.

2Na⁺ + CO₃²- + Ca²⁺ + 2Cl^- ---> CaCO3(s) + 2Na⁺ + 2Cl^-
To get the net ionic equation we simply get rid of the ions that appear on both sides so we are left with

2.Ca²⁺(aq) + CO₃^2–(aq) → CaCO₃(s)

3. No ions are present. As sugan is not dissociated into ions in aqueous solution.