Page 18 - Curriculum Visions Dynamic Book

Acids
Acids, whose name comes from acetum, the Latin for vinegar, are a large and important group of chemicals. They are usually corrosive and have
a sour taste. Acids are grouped into mineral acids, such as sulphuric, nitric and hydrochloric acid, and organic acids (containing carbon), such as tartaric and citric acid.
Mineral acids are produced by many natural processes. For example, acid forms when lightning strikes, as the nitrogen and oxygen in the air
are converted into oxides of nitrogen. When
they dissolve in the water droplets of a cloud,
the result is nitric acid.
Organic acids are produced by living things. One common example is the citric acid produced by citrus fruits, which gives them their sharp taste.
Both mineral and organic acids dissociate to some degree when they are added to water. Acids can also react with some metals to give off hydrogen gas.
 When magnesium ribbon is dropped into dilute hydrochloric acid, a reaction takes place in which hydrogen gas and heat are given off, creating the steam shown in the picture. The metal is being corroded by the acid, as shown by the equation below.
Mineral acids
Mineral acids are acids that do not contain any carbon. The most common mineral acids are hydrochloric, sulphuric and nitric acid.
The mineral acids are called strong acids. They all have a hydrogen atom attached to a nonmetal atom.
Chlorine
EQUATION: The reaction of magnesium with an acid
Magnesium + dilute hydrochloric acid ➪ magnesium chloride + hydrogen gas Mg(s) + 2HCl(aq) ➪ MgCl2(aq) + H2(g)
Hydrogen Magnesium
18