Ionic bonding and ionic compounds

This question is about structure and bonding.

Calcium sulfide is an ionic compound.

Figure 13 represents the structure of calcium sulfide.

Determine the empirical formula of calcium sulfide.

Calcium is in Group 2 of the periodic table.

Sulfur is in Group 6 of the periodic table.

Describe what happens when a calcium atom reacts with a sulfur atom.

Answer in terms of electrons and ions.

Figure 14 shows the structure of graphite.

Describe the structure and bonding of graphite.

Substances that consist of small molecules do not conduct electricity.

Give one reason why.

Methane consists of small molecules.

Poly(ethene) is a polymer.

Why does poly(ethene) have a higher melting point than methane?

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This question is about structure and bonding.

Calcium sulfide is an ionic compound.

Figure 2 represents the structure of calcium sulfide.

Determine the empirical formula of calcium sulfide.

Calcium is in Group 2 of the periodic table.

Sulfur is in Group 6 of the periodic table.

Describe what happens when a calcium atom reacts with a sulfur atom.

Answer in terms of electrons and ions.

Figure 3 shows the structure of graphite.

Describe the structure and bonding of graphite.

Substances that consist of small molecules do not conduct electricity.

Give one reason why.

Methane consists of small molecules.

Poly(ethene) is a polymer.

Why does poly(ethene) have a higher melting point than methane?

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This question is about elements, compounds and mixtures.

Figure 1 shows diagrams which represent the atoms and molecules in different substances.

Which diagram in Figure 1 represents a pure compound?

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Which diagram in Figure 1 represents a mixture of an element and a compound?

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Elements are metals or non-metals.

Figure 2 shows an outline of the periodic table.

The periodic table is divided into sections.

Where are metals found in the periodic table?

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Which two of the following are typical properties of a transition metal?

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Potassium and chlorine react to produce potassium chloride.

An atom of potassium loses an electron to form a potassium ion.

An atom of chlorine gains an electron to form a chloride ion.

Complete the dot and cross diagram.

Mixtures are separated by different methods.

Figure 3 shows the apparatus for separating four different types of mixture.

Figure 3

Which apparatus could be used to collect water from sodium chloride solution?

Use Figure 3.

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Which apparatus shows filtration?

Use Figure 3.

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This question is about ionic compounds and electrolysis.

Calcium chloride is an ionic compound.

Calcium and chlorine react to produce calcium chloride.

Describe what happens to calcium atoms and chlorine atoms when the ionic compound calcium chloride is formed.

Solid calcium chloride cannot be electrolysed.

Give one reason why.

Name the product formed at the negative electrode when aqueous calcium chloride solution is electrolysed.

What is the half equation for the reaction at the positive electrode when aqueous calcium chloride solution is electrolysed?

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A student investigated the electrolysis of green copper chromate solution.

Figure 4 shows the apparatus.

Figure 5 shows the results.

Copper chromate solution contains the ions Cu²⁺ and CrO₄^2–

Explain the results shown in Figure 5.

This question is about small particles.

Which type of particle is often referred to as dust? Tick (✓) one box.

A spherical coarse particle has a diameter of 4000 nm. A spherical fine particle has a diameter of 200 nm. How many times larger is the diameter of the coarse particle than the diameter of the fine particle? Tick (✓) one box.

Figure 6 represents a cubic nanoparticle.

The volume of the cubic nanoparticle is 27 nm³. Calculate:

• the surface area of the cubic nanoparticle

• the simplest whole number ratio of surface area: volume for the cubic nanoparticle.

Use the equation: surface area of cubic nanoparticle = 6 × surface area of one face

Titanium oxide is used in some sun creams.

Which is an advantage of using nanoparticles of titanium oxide rather than normal-sized particles of titanium oxide in sun creams? Tick (✓) one box.

Titanium oxide contains Ti⁴⁺ ions and O²⁻ ions. What is the formula of titanium oxide? Tick (✓) one box.

This question is about ionic compounds and electrolysis. Sodium chloride is an ionic compound.

Figure 8 represents part of the structure of solid sodium chloride.

Complete Figure 8.

Give one reason why molten sodium chloride conducts electricity. Refer to ions in your answer.

Table 3 shows products of the electrolysis of two molten ionic compounds. Complete Table 3.

Aluminium is extracted by electrolysis. The electrolyte is a molten mixture of aluminium oxide and cryolite. Why is a mixture used instead of pure aluminium oxide as the electrolyte? Tick (✓) one box.

Electrolysis of an aqueous solution of sodium sulfate produces hydrogen and oxygen. What is the source of the hydrogen and the oxygen produced during the electrolysis of aqueous sodium sulfate solution? Tick (✓) one box.

Electrolysis of an aqueous solution of sodium sulfate produces hydrogen and oxygen.

Why is hydrogen produced instead of sodium in the electrolysis of aqueous sodium sulfate solution? Tick (✓) one box.

Figure 9 shows the relationship between the volume of hydrogen and the volume of oxygen produced during the electrolysis.

Give one conclusion that can be made about the volume of hydrogen produced compared to the volume of oxygen produced.

This question is about metals and non-metals.

Figure 15 shows an outline of part of the periodic table.

Element Q is a dull solid with a melting point of 44 °C.

Element Q does not conduct electricity.

Which section of the periodic table in Figure 15 is most likely to contain element Q ?

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Element R forms ions of formula R²⁺ and R³⁺

Which section of the periodic table in Figure 15 is most likely to contain element R ?

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Give two differences between the physical properties of the elements in Group 1 and those of the transition elements.

Complete Figure 16 to show the electronic structure of an aluminium atom.

Use the periodic table.

Aluminium is a metal.

Describe how metals conduct electricity.

Answer in terms of electrons.

Name the type of bonding in compounds formed between metals and non-metals.

Magnesium oxide is a compound formed from the metal magnesium and the non-metal oxygen.

Describe what happens when a magnesium atom reacts with an oxygen atom.

You should refer to electrons in your answer.

This question is about metals and non-metals. Figure 1 shows an outline of part of the periodic table.

Element Q is a dull solid with a melting point of 44 °C. Element Q does not conduct electricity. Which section of the periodic table in Figure 1 is most likely to contain element Q ?

Tick (✓) one box.

Element R forms ions of formula R²⁺ and R³⁺ Which section of the periodic table in Figure 1 is most likely to contain element R ?

Tick (✓) one box.

Give two differences between the physical properties of the elements in Group 1 and those of the transition elements.

Complete Figure 2 to show the electronic structure of an aluminium atom. Use the periodic table.

Aluminium is a metal. Describe how metals conduct electricity. Answer in terms of electrons.

Name the type of bonding in compounds formed between metals and non-metals.

Magnesium oxide is a compound formed from the metal magnesium and the non-metal oxygen. Describe what happens when a magnesium atom reacts with an oxygen atom. You should refer to electrons in your answer.

This question is about elements, compounds and mixtures.

Substance A contains only one type of atom.

Substance A does not conduct electricity.

Which type of substance is A ?

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Substance B contains two types of atoms.

The atoms are chemically combined together in fixed proportions.

Which type of substance is B ?

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What is the name of the elements in Group 0 of the periodic table?

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Which statement about the elements in Group 0 is correct?

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Neon is in Group 0.

What type of particles are in a sample of neon?

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Figure 1 represents part of the structure of an oxide of a metal.

Determine the empirical formula of this oxide.

Empirical formula = XO___

A nanoparticle of a metallic element is a cube.

Figure 2 shows a diagram of the nanoparticle.

The surface area of a cube is given by the equation:

surface area = length of side² × 6

Calculate the surface area of the cube in Figure 2.

Give your answer to 2 significant figures.

Fine and coarse particles of the metallic element are also cubes.

The length of a fine particle cube is 10 times smaller than the length of a coarse particle cube.

How does the surface area to volume ratio of the fine particle cube compare with that of the coarse particle cube?

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This question is about Group 1 elements.

Complete Table 2 to show the electronic structure of a potassium atom.

Why do Group 1 elements have similar chemical properties?

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What is the type of bonding in sodium?

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Table 3 shows observations made when lithium, potassium and rubidium react with water.

Give two observations you could make when sodium reacts with water.

Write your answers in Table 3.

How does the reactivity of the elements change going down Group 1?

Give two ways in which the observations in Table 3 show the change in reactivity going down Group 1.

Which gas is produced when Group 1 elements react with water?

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Sodium fluoride is an ionic compound.

Figure 5 shows dot and cross diagrams for a sodium atom and a fluorine atom.

Complete Figure 5 to show what happens when a sodium atom and a fluorine atom react to produce sodium fluoride.

You should:

• complete the electronic structures of the sodium ion and the fluoride ion

• give the charges on the sodium ion and the fluoride ion.

Figure 5

This question is about Group 1 elements.

Give two observations you could make when a small piece of potassium is added to water.

Complete the equation for the reaction of potassium with water. You should balance the equation.

Explain why the reactivity of elements changes going down Group 1.

Sodium reacts with oxygen to produce the ionic compound sodium oxide. Oxygen is a Group 6 element.

Draw a dot and cross diagram to show what happens when atoms of sodium and oxygen react to produce sodium oxide. Diagram

Why is oxygen described as being reduced in the reaction between sodium and oxygen?

Explain why sodium oxide has a high melting point.

This question is about structure and bonding.

Which two substances have intermolecular forces between particles? Tick (✓) two boxes.

Table 5 shows the structures of three compounds.

Compare the structure and bonding of the three compounds:

• carbon dioxide

• magnesium oxide

• silicon dioxide.

This question is about structure and bonding.

Which two substances have intermolecular forces between particles? Tick (✓) two boxes.

Table 1 shows the structures of three compounds.

Compare the structure and bonding of the three compounds:

• carbon dioxide

• magnesium oxide

• silicon dioxide.

This question is about ammonia, NH₃

Complete the dot and cross diagram for the ammonia molecule shown in Figure 6. Show only the electrons in the outer shell of each atom.

Give one limitation of using a dot and cross diagram to represent an ammonia molecule.

Explain why ammonia has a low boiling point. You should refer to structure and bonding in your answer.

Ammonia reacts with oxygen in the presence of a metal oxide catalyst to produce nitrogen and water.

Which metal oxide is most likely to be a catalyst for this reaction? Tick (✓) one box.

Figure 7 shows the displayed formula equation for the reaction.

Table 3 shows some bond energies.

Calculate the overall energy change for the reaction. Use Figure 7 and Table 3.

Explain why the reaction between ammonia and oxygen is exothermic. Use values from your calculation in Question 05.5

Figure 8 shows the reaction profile for the reaction between ammonia and oxygen. Complete Figure 8 by labelling the:

• activation energy

• overall energy change.

This question is about metals and metal compounds.

Iron pyrites is an ionic compound.

Figure 12 shows a structure for iron pyrites.

Determine the formula of iron pyrites.

Use Figure 12.

An atom of iron is represented as⁵⁶₂₆Fe

Give the number of protons, neutrons and electrons in this atom of iron.

Iron is a transition metal.

Sodium is a Group 1 metal.

Give two differences between the properties of iron and sodium.

Nickel is extracted from nickel oxide by reduction with carbon.

Explain why carbon can be used to extract nickel from nickel oxide.

This question is about metals and metal compounds.

Iron pyrites is an ionic compound. Figure 1 shows a structure for iron pyrites.

Determine the formula of iron pyrites. Use Figure 1.

An atom of iron is represented as⁵⁶₂₆Fe Give the number of protons, neutrons and electrons in this atom of iron.

Iron is a transition metal. Sodium is a Group 1 metal. Give two differences between the properties of iron and sodium.

Nickel is extracted from nickel oxide by reduction with carbon.

Explain why carbon can be used to extract nickel from nickel oxide.

An equation for the reaction is:

Calculate the percentage atom economy for the reaction to produce nickel. Relative atomic masses (A_r): C = 12 Ni = 59 Relative formula mass (M_r): NiO = 75 Give your answer to 3 significant figures.