Ionic Bonding Practice Questions

State what is meant by the term ion.

Complete the table by giving the formula, including the charge, of the ion formed by each atom.

element	group	formula of ion formed
lithium	1	$\mathrm{Li^+}$
potassium	1
calcium	2
iodine	7

Iron(III) hydroxide contains $\mathrm{Fe^{3+}}$ ions and $\mathrm{OH^-}$ ions.

Which of these is the formula of iron(III) hydroxide?

Put a cross ( ☒ ) in the box next to your answer.

☐ A $\mathrm{FeOH}$

☐ B $\mathrm{Fe(OH)_2}$

☐ C $\mathrm{Fe(OH)_3}$

☐ D $\mathrm{Fe_3OH}$

Deduce the formula of each of the following compounds.

(i) potassium carbonate, which contains $\mathrm{K^+}$ and $\mathrm{CO_3^{2-}}$ ions

(ii) magnesium nitrate, which contains $\mathrm{Mg^{2+}}$ and $\mathrm{NO_3^-}$ ions

Lithium reacts with bromine to form a compound containing only lithium and bromine.

Name this compound.

Explain what the endings –ide and –ate tell you about the elements present in a compound.

Give the name of the compound with the formula $\mathrm{K_2SO_4}$.

Give the number of protons, neutrons and electrons in one $^{80}_{34}\mathrm{Se^{2-}}$ ion.

protons .............................

neutrons .............................

electrons .............................

A different ion has the formula $\mathrm{X^{2+}}$. This ion contains 18 electrons and 22 neutrons.

Deduce the atomic number and the mass number of element X.

Give the charge on the ion formed by an oxygen atom.

Draw a dot and cross diagram to show the bonding in magnesium oxide.

Show only the outer shell electrons and include the charge on each ion.

Magnesium also reacts with chlorine to form magnesium chloride, $\mathrm{MgCl_2}$.

Explain, in terms of electron transfer, why two chlorine atoms react with each magnesium atom.

Give the electronic configurations of the ions in magnesium sulfide.

$\mathrm{Mg^{2+}}$ ...............................................

$\mathrm{S^{2-}}$ ...............................................

Explain, in terms of electrons, how magnesium sulfide is formed from magnesium atoms and sulfur atoms.

Which of these best describes the structure of solid potassium iodide?

Put a cross ( ☒ ) in the box next to your answer.

☐ A molecules held together by weak forces of attraction

☐ B a regular arrangement of atoms joined by covalent bonds

☐ C a regular arrangement of ions held together by strong electrostatic forces

☐ D positive ions surrounded by a sea of delocalised electrons

Describe the structure of solid potassium iodide, including the forces that hold the structure together.

Calcium reacts with fluorine to form calcium fluoride, $\mathrm{CaF_2}$.

The electronic configuration of a calcium atom is 2.8.8.2 and the electronic configuration of a fluorine atom is 2.7.

Explain how calcium fluoride is formed from calcium atoms and fluorine atoms, and describe the structure of the calcium fluoride produced.

Your answer should refer to the transfer of electrons, the ions formed and the way the ions are arranged and held together.