Revision-Gr-7-Chemistry-Term-2

Burning is a/an ..............................reaction

• endothermic

• exothermic

• precipitation

• physical

.......................... reactions decrease the temperature of surroundings

• exothermic

• burning

• endothermic

• freezing

The substances we start with in a chemical reaction are called the .............................

• products

• chemical equation

• reactants

• salts

When a chemical reaction fizzes, it is usually because it is producing a gas. This is called...…...............

• effervescence

• precipitation

• Combustion

• oxidation

some chemical reactions between solutions produce a solid.This is called a ................... reaction

• effervescence

• precipitation

• combustion

• Oxidation

The simplest particles are called

• molecules

• compounds

• elements

• atoms

The groups of two or more atoms which are joined together are ...........................

• molecules

• compounds

• elements

• atoms

When a gas is cooled it changes to liquid and the process is called

• evaporation

• condensation

• sublimation

• diffusion

The unusual change of state from solid to gas and gas to solid is called ................

• evaporation

• condensation

• sublimation

• diffusion

The change of state from liquid to gas is called...........

• evaporation

• condensation

• sublimation

• diffusion