Revision Final Exams term 1 Science gr.8 Quiz

Which of the following is an example of a chemical change?

• crumpled paper.

• pencil sharpening.

• shrunken clothing.

• baking bread.

In a(an) ………………. Reaction, the energy required is greater than the energy released to break the bonds of the reactants.

• endothermic

• substitution

• exothermic

• oxidation-reduction

A formation of gases is a sign that ……………………

• a chemical change is taking place.

• a physical change has just occurred.

• oxygen is present.

• organic chemicals are present.

A/an …………………… is a system in which matter can't enter or escape from the surrounding.

• closed system

• open system

• isolated system

• chemical system

A ……………………… is the speed at which an object is moving at a given instant in time.

• velocity.

• average speed

• instantaneous speed

• displacement

A shorter, easier way to show chemical reactions, using symbols instead of words, is called a ………………

• chemical equation.

• symbol.

• chemical formula.

• subscript.

A type of reaction formed when compounds break down into simpler products.

• decomposition.

• synthesis

• replacement.

• substitution.

A type of reaction formed When two or more elements or compounds make more complex substance.

• decomposition.

• synthesis

• replacement.

• substitution.

A type of reaction formed When one element replaces another element in a compound

• decomposition.

• synthesis

• replacement.

• substitution.

A change in position relative to a reference point is………………………..

• acceleration

• velocity

• motion.

• speed.