Chem U3 Section titles

The modern periodic table has been developed from work begun by Newlands and Mendeleev. There are trends in the chemical properties within the periodic table linked to how easily the element gains or loses electrons.

The water we drink is not pure water because it contains dissolved substances. It should be safe to drink water that has been treated. This means that the water does not contain anything that could cause us harm, Some of the dissolved substances are beneficial to our health but some cause hard water.

Knowing the amount of energy involved in chemical reactions is useful so that resources are used efficiently and economically. It is possible to measure the amount of energy experimentally or to calculate it. 

A range of chemical tests can be used for the detection and identification of elements and compounds. Titrations can be used to find the amounts of acid or alkali in a solution. 

In industrial processes, energy requirements and emissions need to be considered both for economic reasons and sustainable development.

Alcohols and carboxylic acids are important organic chemicals that have many issues. Alcohols reacts with carboxylic acids to produce esters.