ACIDS AND BASES

Every liquid will probably have some acidic or basic traits. Water can be acidic or basic in different reactions. Water can even react with itself to form acids and bases. The amino acids are named this because they are acidic. Fruits have an acid called citric acid.

When substances are added to water, sometimes they break down and release hydrogen H+ ions. Other times they release an OH- (Hydroxide)ion When the substances break down and release a hydrogen ion, the solution becomes acidic. When the substance breaks down and releases a hydroxide ion, the solution is basic.

The scale goes from 0 up to 14.

When acetic acid is added to water, the molecule CH 3 COOH splits into CH 3 COO - and a H + ion. This is the reason it is called an acid. The pH scale is used to measure how acidic or basic a liquid is. The scale focuses on the concentrations of hydrogen or hydroxide ion present.

Distilled water is 7 on the pH scale. Very strong acids have a value below 1, such as battery acid. Bases with a pH near 14 include drain cleaner and are very dangerous.

Acids and bases can cancel each other out, this is called neutralization. Rain contains small amounts of acid most of the time. When the levels become too high it causes acid rain. Acid rain can cause damage to buildings, sculptures. Coral contains calcium carbonate, a base. This is also found in marble and limestone which make up buildings. When the materials break down they also release CO 2.

Acids and Bases in Solution All formulas for acids begin with Hydrogen. Many are made with one or more positive hydrogen ions and a negative ion. A Hydrogen ion is one that has lost its electron. Acids in water solution separate into hydrogen ions (H + ) and negative ions. HCl→H + + Cl - An acid is any substance that forms hydrogen ions in water.

The strength refers to how well an acid or base separates into ions in water. Strong acids have more hydrogen ions (H + ) are produced. Strong bases break into solutions with more OH - ions

Many bases are made of positive ions combined with hydroxide ions. When bases dissolve in water, the positive ions and hydroxide ions separate. NaOH → Na + + OH -

Not every base contains hydroxide. Ammonia (NH 3 ) does not. In solution ammonia reacts with water to produce hydroxide ions. NH 3 + H 2 O → NH OH - In both reactions, there are positive ions and negative ions in water. A base is any substance that forms hydroxide ions (OH - )in water.