GCSE Chemistry (Single Science)

In a reversible reaction, the products can react to produce the original reactants. The conditions chosen for an industrial reaction are related to producing an acceptable yield in an acceptable time.

Rate of reaction is a measure of how fast a reaction takes place. In industry, chemists control rates of reaction to ensure the production is safe but still fast enough to keep up with demand.

Chemical reactions are reversible and may reach a dynamic equilibrium. The position of equilibrium of a reversible reaction can be altered by changing the reaction conditions.

The greater the frequency of successful collisions between reactant particles, the greater the reaction rate.

Chemical reactions are reversible and may reach a dynamic equilibrium. The direction of some reversible reactions is altered by changing the reaction conditions.

The greater the frequency of successful collisions between reactant particles, the greater the reaction rate. Temperature, concentration, pressure and the use of catalysts affect reaction rate.

No atoms are created or destroyed during a chemical reaction. This allows calculations to be made on the quantities of substances that react and of the products made.

Quantitative analysis is used by chemists to make measurements and calculations. Alkalis neutralise acids to make salts and water. Their concentration can be analysed using titrations.

Exothermic reactions transfer energy to the surroundings and the temperature of the surroundings increases. Endothermic reactions take in energy and the temperature of the surroundings decreases.

Laboratory tests are used to detect and identify gases and ions. Instrumental methods of analysis are faster, more accurate and more sensitive than these simple chemical tests.