Question

Corrosion and redox reactions chem questions - HELP APPRECIATED

QUESTION ONE - In the following chemical reaction, CaO is the reducing agent.

2Ca(s) + O₂ (g) → 2CaO (s)

True
False

QUESTION TWO - What is the oxidation state of Nitrogen in K₃Fe(CN)₆ ?

QUESTION THREE - Identify the correct statement(s) with regards Zinc in Contact with Magnesium experiment

A.

Magnesium metal could be used as a suitable coating for both galvanized and non-galvanized nails to protect both iron and zinc from corrosion.

B.

As the reaction proceeds, Copper metal is deposited on the exposed surface of the nail.

C.

Magnesium is oxidized from Mg(s) to Mg²⁺ when in contact with the Cu(NO₃)₂ solution

D.

Aluminum metal cannot be used instead of magnesium to prevent corrosion of zinc under the same conditions.

E. Magnesium forms a physical barrier prevent the Cu(NO₃)₂ solution from coming into contact with the zinc-plated galvanized nail.

QUESTION FOUR - Which of the following chemical equations correspond to redox reactions? Select all that apply.

A.

NH₃ (aq) + HCl (aq) → NH₄Cl (aq)

B.

2AgOOCCH₃ (aq) + Zn(s) → Zn(OOCCH₃)₂ (aq) + 2Ag(s)

C.

Au(s) + BrF₃ (aq) + KF (aq) → Br₂ (l) + KAuF₄ (aq)

D.

Na₂CO₃ (aq) + H₂SO₄(aq) → 2Na⁺ (aq) + SO₄^2- (aq) + CO₂ (g) + H₂O (l)

E.

KNO₃ (aq) + NaOH (aq) → KOH (aq) + NaNO₃ (aq)

QUESTION FIVE -

Identify the correct statement(s) with regards to the last part of Experiment 6: Zinc in Contact with Magnesium

A.

The addition of sodium chloride is necessary for Cu(NO₃)₂ solution to corrode the zinc-plated galvanized nail

B.

As the reaction proceeds, more zinc metal is deposited on the exposed surface of the nail.

C.

Magnesium forms a physical barrier prevent the Cu(NO₃)₂ solution from coming into contact with the zinc-plated galvanized nail.

D.

Magnesium is oxidized from Mg(s) to Mg²⁺ when in contact with the Cu(NO₃)₂ solution

Magnesium metal is able to shuttle electrons easily to the zinc, thereby reducing the amount of zinc undergoing corrosion from the Cu(NO₃)₂ solution

QUESTION SIX - Make three matches with the following metals and a substance that may act as a suitable sacrificial electrode. All three metals have unique choices, you CANNOT reuse choices (for Example: if you pair Nickel metal with A- you cannot use A again for another metal)

	Nickel metal
	Iron metal
	Silver metal

A.	Iron- sacrificial electrode
B.	Manganese- sacrificial electrode
C.	Gold-sacrificial electrode
D.	Copper - sacrificial electrode
E.	PbSO4 - sacrificial electrode