GCSE Chemistry Bonding questions by topic

Copy and complete the table about the three types of strong bonding.

1. (a)Name the bond type formed between a metal and a non-metal.[1]
2. (b)Name the bond type formed between two non-metals.[1]
3. (c)Name the particles that move to carry charge through a metal.[1]
4. (d)State what happens to electrons in ionic bonding.[1]

Magnesium reacts with chlorine to form magnesium chloride.

1. (a)State the charge on a magnesium ion and explain how it forms.[2]
2. (b)State the charge on a chloride ion and explain how it forms.[2]

The formulae of four substances are listed: NaF, O₂, Cu, H₂O.

1. (a)Which substance contains ionic bonds?[1]
2. (b)Which substance contains metallic bonding?[1]
3. (c)Which two substances contain covalent bonds?[1]
4. (d)Which substance is made of simple molecules?[1]

A student tests four solids with a bulb circuit and finds only one lights the bulb when the solid itself is connected.

1. (a)Identify the solid that lights the bulb and name the charge carriers.[2]
2. (b)The sodium chloride is then melted. Predict whether the molten liquid conducts and explain why.[3]

Water, H₂O, is a simple molecular substance.

1. (a)How many covalent bonds does each oxygen atom form in water?[1]
2. (b)Water boils at 100 °C. State whether the O–H covalent bonds break during boiling.[1]
3. (c)Name the forces that are overcome when water boils.[1]
4. (d)Describe the strength of these forces compared with covalent bonds.[1]

A teacher reads out four descriptions of structures, without naming them.

1. (a)“A giant lattice of alternating positive and negative ions.” Name this structure type.[1]
2. (b)“Small groups of two or more atoms joined by shared pairs of electrons.” Name this structure type.[1]
3. (c)“Layers of positive ions surrounded by a sea of free electrons.” Name this structure type.[1]
4. (d)“One enormous network of atoms, every one joined by shared pairs.” Name this structure type.[1]
5. (e)State which of the four structures conducts electricity when molten but not when solid.[1]

A student draws a dot-and-cross diagram for the formation of lithium oxide from Li (2,1) and O (2,6).

1. (a)State how many lithium atoms are needed per oxygen atom, and why.[2]
2. (b)Describe what the completed diagram shows for each ion, including brackets and charges.[3]
3. (c)Write the formula of lithium oxide.[1]

Explain the following observations about three substances: sodium chloride melts at 801 °C; methane boils at −162 °C; a copper bar can be hammered into a sheet without cracking.

1. (a)Explain sodium chloride’s high melting point.[2]
2. (b)Explain methane’s very low boiling point.[2]
3. (c)Explain the copper bar’s malleability.[2]

Silicon dioxide is a giant covalent solid melting above 1600 °C; carbon dioxide is a simple molecular gas subliming at −78 °C. Both contain covalent bonds.

1. (a)Explain why silicon dioxide melts so much higher than carbon dioxide boils.[3]
2. (b)State whether either substance conducts electricity, with a reason.[2]

Iron rusts when both oxygen and water reach its surface. Ships are protected by bolting on blocks of zinc or painting the hull.

1. (a)Steel ship panels are made from iron alloyed with carbon atoms. Explain why the alloy is harder than pure iron.[3]
2. (b)Explain why pure iron conducts electricity.[2]
3. (c)State one property, other than hardness, that alloying can change.[1]

This question is about drawing covalent bonds in hydrogen sulfide, H₂S (S is in Group 6), and chlorine, Cl₂ (Cl is in Group 7).

1. (a)Draw a dot-and-cross diagram for one molecule of Cl₂, showing outer-shell electrons only.[2]
2. (b)Draw a dot-and-cross diagram for one molecule of H₂S, showing outer-shell electrons only.[3]
3. (c)State the total number of covalent bonds formed by the sulfur atom in H₂S.[1]

An engineer checks a materials database containing magnesium fluoride, hexane, iron and silicon dioxide.

1. (a)Explain why magnesium fluoride conducts only when molten or dissolved.[2]
2. (b)Explain why hexane melts at such a low temperature.[2]
3. (c)Identify which material would suit overhead power cables and justify the choice.[2]

A student compares poly(ethene) sheet and diamond, both made only of carbon and hydrogen or carbon alone, both covalently bonded.

1. (a)Diamond cannot be melted in a school laboratory but poly(ethene) softens at about 120 °C. Explain the difference.[4]
2. (b)Poly(ethene) does not melt sharply but softens over a range. Suggest why.[2]

The table lists data for four substances.

1. (a)Identify the bonding type of each substance, explaining one clue for each.[4]
2. (b)Substance D has an extremely high melting point. State its likely structure type and what melting would have to break.[2]
3. (c)One of the four could be nitrogen. Which, and why?[1]

This question is about models of bonding.

1. (a)A dot-and-cross diagram of HCl shows the shared pair as one dot and one cross. Explain what this diagram falsely suggests about the electrons.[2]
2. (b)A ball-and-stick model of sodium chloride is used to explain its high melting point. Give two limitations of this model for that purpose.[3]
3. (c)Name one feature of a real ionic lattice that no flat diagram can show.[1]

Two demonstrations: a lump of potassium bromide is struck with a hammer and shatters; a beaker of pure water is compared with a beaker of sea water in a conductivity circuit.

1. (a)Explain why the crystal shatters rather than bends.[3]
2. (b)Explain why the pure water does not conduct but the sea water does.[3]

Overhead power cables are made of aluminium strands wound around a steel core.

1. (a)Explain, in terms of particles, why aluminium conducts electricity.[2]
2. (b)Explain why aluminium can be drawn out into long wires without snapping.[2]
3. (c)Aluminium conducts slightly less well than copper. Suggest why aluminium is chosen anyway for long overhead runs.[1]
4. (d)Suggest the purpose of the steel core.[1]

The boiling points of three halogens are compared: chlorine −34 °C, bromine 59 °C, iodine 184 °C.

1. (a)Describe the trend in boiling points down Group 7.[1]
2. (b)Explain the trend in terms of molecules and the forces between them.[3]
3. (c)Predict whether astatine boils above or below 184 °C.[1]
4. (d)State whether molten iodine conducts electricity.[1]