Chemical bonding — IGCSE Chemistry (0620) questions by topic

Which statements about potassium iodide are correct? 1 It is formed from potassium anions and iodide cations. 2 It is a good electrical conductor when molten or in aqueous…

Which substances contain one or more shared pairs of electrons? 1 argon 2 methane 3 iron(III) oxide 4 chlorine A 1 and 3 B 1 and 4 C 2 and 3 D 2 and 4

Which substance has a giant covalent structure at room temperature and pressure? A ammonia B carbon dioxide C diamond D water

When sodium chloride is formed from its elements, each chlorine atom ......1...... one ......2...... . Which words correctly complete gaps 1 and 2? 1 2 --- --- --- A gains…

Which substance has a giant covalent structure? A sodium chloride B ammonia C magnesium chloride D graphite

Rubidium is in Group I of the Periodic Table and bromine is in Group VII of the Periodic Table. Rubidium reacts with bromine to form an ionic compound. Which row shows the…

Which dot-and-cross diagram represents the electronic configuration for the outer shell electrons in ammonia, NH3? Each option (A, B, C, D) shows a dot-and-cross diagram of an…

Which statements about graphite are correct? 1 Each carbon atom is covalently bonded to four other carbon atoms. 2 Graphite is an electrical conductor because it contains ions…

Which statement about potassium chloride is correct? A. It has a high melting point because it is a giant structure with strong covalent bonds. B. It conducts electricity when…

Which dot-and-cross diagram shows the outer shell electron arrangement in a molecule of nitrogen? Four dot-and-cross diagrams (A, B, C, D) each show two overlapping circles…

Which statement about silicon(IV) oxide is correct? A. It contains silicon ions and oxide ions arranged in a giant lattice. B. It is used in electrical circuits because it can…

Which statement about silicon(IV) oxide, SiO2, is correct? A It conducts electricity because it contains delocalised electrons. B It has a giant covalent structure with each…

Which statement about ionic compounds is correct? A Giant lattices are formed when ionic compounds crystallise from solution. B In all ionic compounds, the metal ions have fewer…

The equation for the reaction between iron(III) chloride and sodium hydroxide is shown. FeCl3(aq) + 3NaOH(aq) - Fe(OH)3(s) + 3NaCl(aq) What is the ionic equation for this…

A list of substances is shown: aluminium, bromine, calcium, carbon dioxide, iron, magnesium, magnesium oxide, neon, oxygen, potassium, sulfur dioxide. Each substance may be used…

A list of substances is shown: calcium, calcium oxide, carbon, carbon dioxide, chlorine, copper, gold, iodine, neon, nitrogen, oxygen, potassium, sulfur dioxide. Each substance…

This question is about nitrogen and its compounds. Nitrogen contains molecules with the formula N2. Complete the dot-and-cross diagram in Fig. 4.1 to show the electronic…

This question is about covalent compounds. State what is meant by a covalent bond.

Using the list of substances (aluminium oxide, calcium oxide, chlorine, ethanol, graphite, nitrogen, oxygen, propane, propene, silicon(IV) oxide), state which of the substances is…

Some properties of substances W, X, Y and Z are shown (melting point / °C; electrical conductivity): W: 801; conducts when molten X: -182; does not conduct Y: 840; conducts when…

Atoms lose or gain electrons to become ions. Which row is correct? (columns: change to the atom; type of ion; charge on ion) A loss of two electrons; cation; 2- B loss of one…

Which substance has a giant covalent structure? A sodium chloride B sodium C ethane D diamond

The electronic configurations of four atoms, W, X, Y and Z, are shown: W 2; X 2,6; Y 2,8,2; Z 2,8,6. Which atoms form an ion with a charge of 2- when they react? A W and Y B W…

Which statement about bonding is correct? A All the atoms in CH4, NH3 and H2O molecules have noble gas electronic configurations. B Calcium chloride is a covalent molecule. C…

Which statement about diamond is correct? A It is a giant covalent structure consisting of carbon atoms and each atom is bonded to four other atoms. B It is a giant covalent…

Which row describes the electrical conductivity of covalent and ionic compounds when solid and when molten (✓ = good conductivity, ✗ = poor conductivity)? (columns: covalent…

Which statement about the bonding in sodium chloride is correct? A The sodium and chlorine atoms share pairs of electrons. B The chlorine atoms give electrons to the sodium atoms…

The diagram shows the arrangement of carbon atoms in a giant covalent structure (each carbon atom bonded to four others in a tetrahedral lattice). Which row identifies the…

Which statements about potassium chloride are correct? 1 It conducts electricity when solid because its ions are free to move. 2 It has a high melting point because it has strong…

Information about four substances, W, X, Y and Z, is shown (melting point / °C; electrical conductivity): W 1710, does not conduct when solid; X 3500, conducts when solid; Y 120,…

Silicon(IV) oxide is a covalently bonded compound. Which statements are correct? 1 Silicon atoms form four single bonds in silicon(IV) oxide. 2 Oxygen atoms form two double bonds…

Blood plasma is the liquid part of blood. Table 2.1 shows the mass, in mg, of some ions present in 100 cm³ of blood plasma (name of ion; formula of ion; mass / mg): calcium Ca²⁺…

Intracellular fluid is the solution between the cells in the human body. Table 2.1 shows the masses, in mg, of some ions in 100 cm³ of intracellular fluid (name of ion; formula;…

A list of five metals is shown: copper, iron, magnesium, potassium, silver. All metals form positive ions. Describe how atoms form positive ions.

This question is about elements and compounds. Some properties of graphite, oxygen and carbon monoxide are shown in Table 3.1 (melting point / °C; boiling point / °C; conduction…

Chlorine reacts with sodium to form sodium chloride. What happens to the sodium atoms during this reaction? A They gain electrons to form anions. B They lose electrons to form…

Covalent bonds are formed when electrons are ......1...... . Most covalent compounds have ......2...... electrical conductivity. Which words correctly complete gaps 1 and 2? 1 2…

Which row describes the structure and a use of diamond? structure use --- --- --- A ionic in cutting tools B ionic as a lubricant C giant covalent in cutting tools D giant…

Which row gives the number of covalent bonds in one molecule of ammonia and in one molecule of hydrogen chloride? ammonia hydrogen chloride --- --- --- A 3 1 B 3 2 C 4 1 D 4 2

Which statements about the structure and bonding in diamond are correct? 1 Each carbon atom in diamond is bonded to three other carbon atoms only. 2 Diamond contains many strong…

The diagram shows part of an ionic lattice structure, a regular grid alternating + and - ions in a 1:1 ratio. Which compound does the diagram represent? A potassium bromide B…

Which statement about nitrogen molecules and ethene molecules is correct? A A nitrogen molecule has 2 more shared electrons than an ethene molecule. B An ethene molecule has 3…

Which row identifies a property and an explanation of the property for both diamond and silicon(IV) oxide? property explanation of property --- --- --- A very hard diamond has a…

Which pair of elements react to form a compound with a strong attraction between oppositely charged ions? A carbon and bromine B carbon and nitrogen C sodium and oxygen D sodium…

Which diagram shows the covalent bonding in a molecule of carbon dioxide? A O-C-O B O=C-O C O=C=O D O≡C≡O

The bonding, structure and melting point of sodium chloride and sulfur dichloride are shown: sodium chloride is ionic, giant lattice, melting point 801 °C; sulfur dichloride is…

Diamond and graphite have giant covalent structures of carbon atoms. Which statement describes graphite? A It has a strong, rigid three-dimensional structure. B It has four strong…

What happens when sodium atoms combine with chlorine atoms to form sodium chloride? A Sodium atoms each gain one electron, and chlorine atoms each lose one electron. B Sodium…

The table shows some properties of four substances. substance melting point electrical conductivity when solid electrical conductivity when molten --- --- --- --- 1 high poor poor…

Which statement about methane is correct? A In methane, positive hydrogen ions are attracted to negative carbon ions. B In methane, electrons are shared between carbon atoms and…

The formulae of the molecules A to I are shown in Table 1.1: A C2H4; B C2H5OH; C CO; D CO2; E Cl2; F NO2; G N2; H O2; I SO2. Answer the following questions about the molecules A…

This question is about chlorine and compounds of chlorine. Chlorine has diatomic molecules. Define the term diatomic.

Answer the following questions using only the elements in Fig. 1.1. Each symbol of the element may be used once, more than once or not at all. Give the symbol of the element that…

This question is about ionic and covalent compounds. Sodium reacts with oxygen to form the ionic compound sodium oxide. The electronic configurations of an atom of sodium and an…

Magnesium forms ionic compounds. Magnesium reacts with fluorine to form the ionic compound magnesium fluoride. The electronic configurations of an atom of magnesium and an atom of…

Lithium bromide is a compound with ionic bonding. State the meaning of the term ionic bond.

Zinc chloride is an ionic compound. Ionic compounds are good electrical conductors when molten or in aqueous solution. Describe one other physical property of ionic compounds.

Potassium chloride is an ionic compound. Complete Fig. 8.1 to show the electronic configuration of a potassium ion and the charge on the ion. (Fig. 8.1 shows a K symbol with empty…