Year 9 Chemical World Review

What is all matter made of?

• compounds

• atoms

• pollen

• molecules

What is the centre of an atom called?

• neutron

• electron

• nucleus

• proton

Electrons carry a:

• positive charge

• positive charge on one side and negative charge on the other

• negative charge

• neutral charge

What does the nucleus of an atom consist of?

• positive and negative charges

• protons and electrons

• neutrons and electrons

• protons and neutrons

An isotope of an atom occurs when:

• an atom gains or loses electrons

• the atomic mass of an element has two options

• the number of the protons in the nucleus varies

• the number of neutrons in the nucleus varies

According to the Bohr model of the atom, electrons:

• cannot exist in the electron shells

• are mostly blue

• are in the nucleus

• move in orbits called electron shells

If a helium atom has two protons, how many electrons should it have?

• 2

• 4

• 1

• 0

What does subatomic mean?

• Something underneath atoms

• The spaces between atoms in a molecule or compound

• Atoms that only exist at the depths of the oceans

• Something smaller than an atom

Elements in the periodic table are ordered according to:

• atomic number

• mass number

• the size of their nucleus

• relative atomic mass

What did the gold foil experiment show?

• That all high-energy alpha particles pass through a atom in a straight line

• That some high-energy alpha particles pass through the centre of an atom

• All of the high-energy alpha particles were deflected from an atom

• Some of the high-energy alpha particles were deflected from the centre