Complete the sentences about the structure of an atom. Use words from the list below:

electrons, negative, neutral, neutrons, positive, protons

An atom has orbiting particles called .................... which have a .................... charge. The nucleus has a .................... charge.

Look at the information about two isotopes of nitrogen:

$Isotope\; 1:{}_7^{14}NIsotope\; 2:{}_7^{15}N$

Which two statements about the isotopes of nitrogen are correct?

• Nitrogen has 14 protons.
• The atomic number of nitrogen is 7.
• The electrons are heavier than the protons.
• The isotopes of nitrogen have different numbers of neutrons.
• The isotopes of nitrogen have different numbers of protons.
• The mass number is the same for both isotopes.

The diagram shows a nitrogen atom.

Draw on this

Explain why nitrogen is in Group 5 of the Periodic Table.

Nitrogen is in Group 5 of the Periodic Table. Nitrogen is a non-metal.

Why do non-metals form negative ions?

Nitrogen reacts with magnesium to form magnesium nitride.

• The formula for magnesium nitride is ${Mg}_3{N}_2$.
• The symbol for a magnesium ion is ${Mg}^{2+}$.

What is the symbol for a nitride ion?