Page 26 - Curriculum Visions Dynamic Book

Sulphuric acid
Sulphuric acid, a colourless, thick, heavy and “oily” liquid, is one of the most common acids used in industry and the laboratory. It is a strong mineral acid.
Dilute sulphuric acid will react with most metals to form sulphate compounds and release hydrogen gas. It reacts with bases to form sulphates and water only.
Concentrated sulphuric acid is also a dehydrating agent, that is, it will remove water from other compounds. For example, if a piece of sugar is placed in sulphuric acid it becomes a black lump of carbon, as all the water is removed from the sugar molecules.
If sulphuric acid touches human skin, the molecules in the skin immediately begin to lose water. This is an acid burn.
 Sulphuric acid reacts with metals such as zinc to produce a sulphate of the metal and release hydrogen gas.
Also...
When water and a concentrated acid mix, a huge amount of heat is given off. Water should never be added to concentrated acid. Rather, the acid should be stirred slowly into the water. If water is added to the acid, the water will immediately start to boil causing it to splash out much like hot fat in a fryer. The result could be dangerous acid burns.
EQUATION: Reaction of dilute sulphuric acid and zinc metal
Sulphuric acid + zinc ➪ zinc sulphate + hydrogen H2SO4(aq) + Zn(s) ➪ ZnSO4(aq) + H2(g)
A dehydrating agent
The demonstration on these two pages shows how water can be removed from sugar by dehydration using sulphuric acid.
 A layer of sugar is placed in a beaker and concentrated sulphuric acid is added.
EQUATION: Dehydration of sucrose using concentrated sulphuric acid
Sucrose + sulphuric acid ➪ steam + carbon + sulphuric acid C12H22O11(s) + H2SO4(l) ➪ 11H2O(g) + 12C(s) + H2SO4(aq)
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