Changes

Melting is ...

• liquid to solid
• solid to liquid
• solid to gas
• gas to liquid

The phase change from water vapor to liquid water is known as...

• evaporation
• precipitation
• condensation
• sublimation

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

• heating glass and bending it

• melting an ice

• burning of wood

• boil water

iron + sulfur --> iron sulfide

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

• iron

• iron and sulfur

• sulfur

• iron sulfide

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

• CO₂

• CO

• C

• O₂

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

• Heat is produced

• A gas is given off

• No new substances

. ........ is formed when iron reacts with oxygen in the air

• iroxy

• rust

• crumble

• substances

sodium carbonate + hydrochloric acid → sodium chloride + water + carbon dioxide

Which product contains the element hydrogen?

• hydrochoric acid

• water

• carbon dioxide

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A change in matter that forms one or more new substances with new chemical properties is a/an...

• Physical Change
• Chemical Change