Material Changes Quiz

In a chemical change, new substances are formed, for example

• burning of wood

• heating glass and bending it

• boil water

• melting an ice

iron + sulfur --> iron sulfide

from that word equation, the reactant(s) is/are ....

• iron

• sulfur

• iron and sulfur

• iron sulfide

when something burns, it reacts with the .... in the air

• CO₂

• CO

• O₂

• C

In burning Magnesium ribbon, do not look directly at the flame. Because

• it can burn our eyes

• it can melt our eyes

• Magnesium burns very brightly and the light could harm our eyes

• it can warm our eyes

When magnesium reacts with hydrochloric acid, gas are given off. The gas is .......

• Oxygen

• Hydrogen

• Carbon dioxide

• Carbon monoxide

When the hydrogen pops, it is reacting with oxygen to form .....

• water

• gas

• ash

• pop

zinc +sulfuric acid ---> ....... + hydrogen

• zincate

• zinc acid

• zinc sulfate

• sulfate

Copper carbonate + hydrochloric acid --->

• Copper chloride + water + carbon dioxide

• Copper chloride

• water

• carbon dioxide

What happens in a chemical reaction?

• Atoms form new combinations

• Atoms do not form new combinations

In detecting chemical reactions, there are few clues we can look, except ...

• A colour change

• A gas is given off

• Heat is produced

• No new substances