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Which of these cell diagrams correctly represents a cell in which this reaction is happening?

Mg(s) + Cu²⁺(aq) → Mg²⁺(aq) + Cu(s)

Mg²⁺(aq) | Mg(s) || Cu(s) | Cu²⁺(aq)

Cu(s) | Cu²⁺(aq) || Mg²⁺(aq) | Mg(s)

Mg(s) | Mg²⁺(aq) || Cu(s) | Cu²⁺(aq)

0%✨

Mg²⁺(aq) | Mg(s) || Cu²⁺(aq) | Cu(s)

Mg(s) | Mg²⁺(aq) || Cu²⁺(aq) | Cu(s)

100%

Consider an iron nail with silver wrapped onto it, immersed in an agar gel containing phenolphthalein and potassium ferricyanide. After a few minutes a pink colour appeared in the gel around the silver metal and a blue colour was observed in the gel near the tip and head of the iron nail. What is the most accurate interpretation of these observations?

Iron is oxidised, producing Fe²⁺(aq) at the tip and head of the nail. Oxygen is reduced at the silver to produce OH^–(aq).

Iron is oxidised producing Fe²⁺(aq) at the tip and head of the nail. Ag⁺(aq) is reduced producing silver metal.

Silver is oxidised producing Ag⁺(aq). Water is reduced at the iron nail to produce OH^–(aq).

Silver is oxidised, producing Ag⁺(aq). Oxygen is reduced at the silver to produce OH^–(aq).

Iron is oxidised at the tip and head of the nail, producing Fe²⁺(aq). Water is reduced at the silver to produce OH^–(aq).

A galvanic cell constructed using an X⁺|X electrode connected to a standard copper half–cell (as used in this experiment) was found to have a cell potential of 0.45 V with the X⁺|X electrode being negative with respect to the copper electrode. Where on the number line below would you place the X⁺|X electrode?

representation of half-cell potentials on a number line

A galvanic cell was constructed where one electrode was a Cu²⁺(aq)|Cu(s) electrode and the other was an M²⁺(aq)|M(s) electrode. The potential difference between the two electrodes was measured to be 0.27 V with the copper electrode being the more positive electrode. What is the potential of the M²⁺(aq)|M(s) electrode with respect to the standard hydrogen electrode?

Data: E°(Cu²⁺(aq)|Cu(s)) = +0.34 V

Consider an iron nail with magnesium wrapped onto it, immersed in an agar gel containing phenolphthalein and potassium ferricyanide. After a few minutes a pink colour appeared in the gel around the iron nail and but no blue colour was observed in the gel. What is the most accurate interpretation of these observations?

Magnesium is oxidised producing Mg²⁺(aq). Water is reduced at the nail to produce OH^–(aq).

Iron is oxidised along the shaft of the nail, producing Fe²⁺(aq). Water is reduced at the magnesium to produce OH^–(aq).

Magnesium is oxidised producing Mg²⁺(aq). Oxygen is reduced at the nail to produce OH^–(aq).

100%

Iron metal is oxidised, producing Fe²⁺(aq). Oxygen is reduced at the magnesium to produce OH^–(aq).

Iron is oxidised producing Fe²⁺(aq). Mg²⁺(aq) is reduced producing magnesium metal.

In the corrosion experiment you will prepare iron nails which are in good contact with a piece of another metal. How will you do this?

Wrap a piece of the metal around a cleaned iron nail.

❌✨

Wrap a piece of the metal around a regular iron nail.

50%

Use a hammer and a cleaned nail to punch a hole through the metal and then insert the nail through the hole.

Use a hammer and a regular nail to punch a hole through the metal and then insert a cleaned nail through the hole.

50%

Which of these most accurately describes how the iron nails will be cleaned in this experiment?

scrub with sandpaper

rinse in tap water only

rinse in sulfuric acid only

rinse in sulfuric acid followed by rinse in tap water, then rinse in boiling water

✅✨

To avoid burns when preparing the agar solution which of these must be not touched until it has cooled? Only select correct answers, selecting incorrect answers will result in a reduced mark.

wire gauze

heat-proof mat

metal ring supporting the wire gauze

beaker containing the agar solution

✅✨