Year 9 Chemistry

Which is the best definition for an ion?

• An atom has a net charge greater or less than zero.
• An ion has the same number of electrons as an atom of the same element.
• An ion has a net charge greater or less than zero.
• There is no difference

If an element has 5 protons and 5 electrons, what is its net charge?

• +5
• -5
• 0
• -1

The group of an element tells us...

• The number of protons
• The number of electron shells
• The number of valence electrons
• The number of total electrons

Sulfuric acid _(aq) + Potassium hydroxide _(aq) → Potassium sulfate _(aq) + Water

• Precipitation

• Neutralisation

• Decomposition

• Acid-metal

Acids have pH values of

• 7
• less than 7
• more than 7
• 14

The positive particles of an atom are 

• electrons 
• positrons 
• neutrons 
• protons 

the central region of an atom where its neutrons and protons are is its 

• nucleus 
• electron cloud
• core 
• center 

an atom with atomic number 6 would have how many protons 

• 6
• 12
• 3
• cannot be determined 

When an atom loses a valence electron, it becomes a(n) _____________ ion.

• positive
• negative
• neutral
• polyatomic

When an atom gains a valence electron, it becomes a(n) _____________ ion.

• positive
• negative
• neutral
• polyatomic