Carbonates

Question 1

Precipitation

Answer 1

Dissolved ions react with each other to form a solid compound. For example, solid calcium carbonate dissolves into calcium and carbonate ions.

Question 2

Acid/base

Answer 2

Acid/base reactions are a special type of ionisation reaction where a hydrogen ion is added to or removed from a solution. For example, hydrochloric acid is added to or removed from a solution.

Question 3

Ion association

Answer 3

Ion association reactions occur when dissolved ions form ties with each other within the solution.

Question 4

Oxidation/reduction

Answer 4

Oxidation/reduction involves valence changes and transfer of electrons. For example iron corrosion releases electrons.

Question 5

Acids

Answer 5

Compounds which release hydrogen ions.

Question 6

Bases

Answer 6

Compounds which accept hydrogen ions.

Question 7

pH

Answer 7

The strength of acidity of baseness is measured on the pH scale, which measures the concentration of hydrogen ions present.

Question 8

Chemical Equilibria

Answer 8

When the rates of reactions are the same, the reaction is said to have reached equilibrium.

Question 9

Strong acids

Answer 9

Strong acids tend to donate hydrogen ions to water. They can be used for water treatment for pH adjustment and coagulation.

Question 10

Weak acids

Answer 10

These do not completely dissociate in water.

Question 11

Buffering Capacity

Answer 11

The ability of a water system to resist pH change.

Question 12

The Carbonate system

Answer 12

This is the most important acid-base system in natural waters. The carbonate system comprises of carbon dioxide, carbonic acid, bicarbonate ions and carbonate ions.

Question 13

Alkalinity

Answer 13

The sum of all titratable bases down to pH 4.5. The contributors to alkalinity are cabonates, hydrogen ions and the hydroxide ion.