8F Periodic Table

Which of the following statements about Dalton's atomic theory is incorrect?

• all matter is made up of tiny particles called atoms

• the atoms of the same element are all different from each other

• atoms cannot be created or destroyed

• in a chemical reaction, atoms are rearranged to make new substances

Which of the following are physical properites

• colour

• melting point

• conductivity fo heat

• flammability

Which of the following is an example of a change that can be easily reversed?

• melting ice

• tearing up paper

• burning paper

• oxidation

What always happens in a chemical reaction?

• new substances are formed

• gas is given off

• colour changes

• energy is released or absorbed

If 4 g of copper fully react with 1 g of oxyegn, how much copper oxide would be forned?

• 5 g

• 3 g

• 4 g

• 1 g

How many atoms are there in a molecule of methane (CH₄)?

• 5

• 4

• 2

• 10

What is th ratio of lithium to oxygen in lithium oxide (Li₂O)?

• 2:1

• 1:2

• 1:2

• depends on how many atoms there are in total

Which of the following is a chemical property?

• reaction with acid

• boiling point

• flexibility

• density

Which of the following properties could be used to describe the alkali metals?

• soft

• hard

• react with water to produce oxygen gas

• shiny when cut

• react with water to produce hydrogen gas

The noble gases are

• unreactive

• very reactive

• explosive

• liquids