2 4 reactivity series

The general equation for a metal reacting with an acid is: metal + acid → salt + hydrogen

True. Only metals above hydrogen in the reactivity series will react with dilute acids.

A salt is the ionic compound produced when a metal reacts with an acid.

The equation for the reaction of calcium with water is: Ca (s) + 2H2O (l) → Ca(OH)2 (aq) + H2 (g)

A displacement reaction is one where a more reactive element takes the place of a less reactive one in a compound.

False. Copper is less reactive than hydrogen.

False. Magnesium reacts very slowly with cold water.

The products when potassium reacts with water are potassium hydroxide and hydrogen gas.

False. Potassium is more reactive than sodium.

If a metal-acid reaction is described as "vigorous", it means the reaction is rapid and intense

False. A more reactive metal will displace a less reactive metal from its compounds.

A reducing agent is a substance that donates electrons in a redox reaction.

The balanced symbol equation is: Zn + CuO → ZnO + Cu

Oxidation is any reaction in which a substance gains oxygen.

Displacement means the removal or replacement of one element/compound by another.

A spectator ion is an ion that does not participate in the chemical reaction and appears unchanged on both sides of the equation.

True. Magnesium can displace copper from copper sulfate solution.

Reduction is a reaction in which a substance loses oxygen.

When a more reactive metal displaces a less reactive one, the less reactive metal coats the surface or falls out as a solid.

If a metal "disappears" from a salt solution, it means it has been displaced by a more reactive metal.

A metal that is above carbon in the reactivity series is:

A metal that is below hydrogen in the reactivity series is:

Zinc is more reactive than iron.

Aluminium is more reactive than zinc.

One mnemonic to remember the reactivity series is: “Please send lions, cats, monkeys and cute zebras into hot countries signed Gordon” Potassium, sodium, lithium, calcium, magnesium, carbon, zinc, iron, hydrogen, copper, silver and gold

False. The least reactive metal is at the bottom of the reactivity series

Rust is the hydrated iron(III) oxide that forms on iron when it corrodes.

True. Rusting requires both oxygen and water to occur.

The term corrosion means the degradation or deterioration of a metal surface through a chemical reaction.

The presence of salt (sodium chloride) speeds up the rusting process.

False. Iron requires the presence of water to rust.

When a more reactive metal is intentionally allowed to corrode to protect another metal, it is called sacrificial corrosion.

Oxidation is the loss of electrons by a substance.

When zinc coats iron, zinc carbonate (ZnCO3) is formed which protects the iron.

True. Rusting weakens the structure and integrity of iron over time as more iron is lost.

Some barrier methods that prevent rusting are:

Oxidation is any reaction in which a substance gains oxygen.

Reduction is a reaction in which a substance loses oxygen.

In Zn + CuO → ZnO + Cu, the zinc / Zn is oxidised as it gains oxygen to become zinc oxide / ZnO.

Oxidation is the loss of electrons.

Reduction is the gain of electrons.

In Mg + Cu2+ → Mg2+ + Cu, magnesium (Mg) is oxidised as it loses electrons.

Spectator ions are ions that appear unchanged on both sides of a chemical equation and do not participate in the reaction.

In terms of electrons, an oxidising agent is a chemical species that accepts electrons. An oxidising agent is reduced.

A redox reaction is when oxidation and reduction take place simultaneously.

The oxidising agent in the following reaction is Ag+ as it has been reduced / gained electrons. Cu + 2Ag+ → Cu2+ + 2Ag