Year 8 MC Quiz Sem 2

Choose the example of a physical change.

• Melting

• Boiling

• Freezing

• All of the above

As a candle burns, the chemical change is:

• the light from the flame.

• the wax melting.

• the burning of the wax.

• the heat being produced.

As two clear solutions sodium sulfate and barium nitrate are combined, a cloudy white powder forms. Choose the best evidence of a chemical change.

• A new solid substance being formed

• Heat given off

• An energy change

• Gas being produced

Here is a word equation for a reaction: magnesium + hydrochloric acid → hydrogen + magnesium chloride. Choose the sentence which best matches the word equation.

• Magnesium reacts with hydrochloric acid to form hydrogen and magnesium chloride.

• Hydrogen reacts with magnesium chloride to form magnesium and hydrochloric acid.

• Magnesium reacts with hydrogen to form hydrochloric acid and magnesium chloride.

• Hydrochloric acid and hydrogen react to form magnesium and magnesium chloride.

When effervescence (fizzing) occurs during a chemical reaction it means that:

• the reactants are heating up.

• a gas is being produced.

• energy is being absorbed by the reactants.

• a salt is being produced.

A molecule is always made up of:

• Two or more atoms.

• One kind of element.

• Two or more elements.

• One atom only.

Which scientist conducted the famous “Gold Foil Experiment”?

• Dalton

• Thomson

• Rutherford

• Bohr

Which scientist devised the “Plum Pudding Model” for the atom?

• Dalton

• Thomson

• Rutherford

• Bohr

What is the name of the type of reaction where one substance is broken down into two or more substances?

• Decomposition

• Synthesis

• Precipitation

• Combustion

What is the name of the type of reaction where a substance burns in the presence of oxygen?

• Decomposition

• Synthesis

• Precipitation

• Combustion