Ionic bonding and ionic compounds

Lithium is an alkali metal.

State which group of the periodic table contains the alkali metals.

Which of the following is a property of lithium?

A teacher adds a small piece of lithium to water containing universal indicator.

The universal indicator changes colour.

State the colour change shown by the universal indicator.

When lithium is added to water, lithium hydroxide and a gas are produced.

What is the name of the gas produced in this reaction?

Lithium hydroxide contains lithium ions, Li⁺.

Describe how a lithium atom becomes a lithium ion.

Calculate the percentage by mass of hydrogen in lithium hydroxide, LiOH.

(relative atomic masses: Li = 7, O = 16, H = 1.0)

Group 1 elements are known as the alkali metals.

Which row gives two physical properties of the alkali metals?

The alkali metals react with water.

A teacher adds a small piece of potassium to water.

Give two observations that would be seen.

The reaction of lithium with water is much less vigorous than the reaction of potassium with water.

Explain why, in terms of their electronic configurations.

When sodium reacts with water, a solution of sodium hydroxide is formed.

When the solution is left in air, the hydroxide ions react with carbon dioxide, forming carbonate ions, CO₃^2–, and one other product.

Complete the ionic equation for this reaction.

_........ OH^– +_........ CO₃^2– +_........

The relative atomic mass of caesium is 132.905.

Calculate the average mass of one atom of caesium

(Avogadro constant = 6.02 × 10²³)

mass =_........ g

Water treatment is needed to make most sources of water suitable for drinking.

Water treatment includes the processes of chlorination, filtration and sedimentation.

Place these processes in the order that they take place during water treatment.

Some tap water contains chloride ions.

Explain, in terms of electrons, how a chlorine atom, C l, forms a chloride ion, Cl^–.

Why is chlorine added to water during water treatment?

State why tap water is not suitable for use in chemical analysis.

A student was asked to distil a sample of tap water. Figure 4 shows the apparatus the student used.

The student made an error when setting up the apparatus in Figure 4.

This error meant that pure water could not be collected in the test tube.

Explain what the student needs to change so that pure water can be collected in the test tube.

State what the student should use to heat the water.

Sodium carbonate has the formula Na₂CO₃.

Sodium carbonate contains Na⁺ ions and CO₃^2– ions.

The atomic number of sodium is 11.

What is the electronic configuration of the Na⁺ ion?

Explain why solid sodium carbonate cannot conduct electricity but a solution of sodium carbonate can conduct electricity.

Calculate the percentage by mass of sodium in sodium carbonate, Na₂CO₃.

(relative atomic masses: C = 12, O = 16, Na = 23)

percentage by mass of sodium =_........

*(c) A student has three solids, A, B and C.

The solids are sodium carbonate, powdered zinc and copper oxide, but the student does not know which solid is which.

The student reacted each solid with dilute sulfuric acid.

Figure 9 shows the student’s observations and the results of tests on any gases produced.

Use the observations and results in Figure 9 to identify which solid is which.

Your answer should include

• how each test result helps you to identify the solid

• word equations to support your answer.

This question is about the extraction of metals.

Give two advantages of obtaining metals by recycling rather than by extracting them from their metal ores.

Small amounts of some metals are extracted using displacement reactions.

In one process, zinc dust is used to precipitate cadmium metal from a solution containing cadmium ions.

cadmium ions
cadmium

Explain why this displacement reaction can be described as a redox reaction.

The formula of the cadmium ion is Cd²⁺. The formula of the phosphate ion is PO₄^3–.

Which is the formula of cadmium phosphate?

One of the alternative biological methods of extracting metals from very low‑grade ores is bioleaching using bacteria.

Give one disadvantage of this method of extracting metals from low‑grade ores.

Lead is low in the reactivity series.

Describe how to obtain a sample of lead from some lead oxide in the laboratory.

In one reaction the temperature of the reaction mixture decreases.

Which word describes this type of reaction?

In an experiment, a salt is dissolved in water.

The temperature change is measured.

Figure 3 shows the apparatus that is used.

State what is used to measure the temperature change in Figure 3.

State one reason for using the piece of equipment A in Figure 3.

A student suggests putting a lid on piece of equipment B.

State why this would help to give a more accurate value for the temperature change.

Four different salts, P, Q, R and S, are dissolved in water.

Figure 4 shows the starting temperature of the water and the final temperature of the solution after the salt dissolves.

Complete the table

• to show the temperature changes when salt R and salt S dissolve

• by placing a tick (✓) in the box, on the bottom row, for the salt that absorbs the most heat energy when it dissolves.

One of the salts dissolved is barium chloride, BaCl₂.

Barium chloride contains the chloride ion, Cl^–.

Give the formula of the barium ion in barium chloride.

Magnesium is a metal.

State one physical property of magnesium.

Which element is in the same group of the periodic table as magnesium? Use the periodic table to help you answer this question.

Magnesium atoms have 12 electrons.

Complete the electronic configuration of a magnesium atom.

The electronic configuration of a chlorine atom is 2.8.7

Explain how the electronic configuration of chlorine is linked to its period in the periodic table.

1.20 g of magnesium reacts completely with 3.55 g of chlorine to form magnesium chloride.

Calculate the empirical formula of the magnesium chloride.

(relative atomic masses: Mg = 24.0, C l = 35.5)

You must show your working.

empirical formula =_........

Sodium reacts with chlorine to form sodium chloride, which contains ionic bonds.

Hydrogen reacts with chlorine to form hydrogen chloride, which contains covalent bonds.

Figure 6 shows dot and cross diagrams of these compounds.

Describe the differences between an ionic bond and a covalent bond.

Chlorine is an element in group 7 of the periodic table.

What name is given to group 7 of the periodic table?

Chlorine reacts with sodium to form sodium chloride.

Write the word equation for this reaction.

Chlorine, Cl₂, is made of simple molecules.

Describe what is meant by the term molecule.

Sodium, like all metals, conducts electricity.

Explain how sodium conducts electricity.

Sodium chloride contains sodium ions, Na⁺, and chloride ions, Cl^–.

Use this information to state the formula of sodium chloride.

Sodium chloride is made of a giant structure of ions.

Which diagram shows the arrangement of particles in sodium chloride?

Sodium chloride solution conducts electricity.

State what can be put into the circuit in Figure 8 to show that a current is flowing.

Figure 9 shows a flow diagram of how hydrochloric acid can be made.

Balance the equation for the reaction between hydrogen and chlorine to form hydrogen chloride.

H₂ + Cl_{2 ........} HCl

State how hydrogen chloride can be converted into hydrochloric acid.

Magnesium carbonate has the formula MgCO₃.

Magnesium carbonate contains Mg²⁺ and CO₃²⁻ ions.

The atomic number of magnesium is 12.

What is the electronic configuration of the Mg²⁺ ion?

Explain why solid magnesium carbonate cannot conduct electricity but solid magnesium can.

Calculate the percentage by mass of magnesium in magnesium carbonate, MgCO₃.

(relative atomic masses: C = 12.0, O = 16.0, Mg = 24.0)

percentage by mass of magnesium =_........

*(c) A student has two separate test tubes containing sulfuric acid.

The student adds a spatula measure of magnesium carbonate, MgCO₃, to the first test tube and a piece of magnesium to the second test tube.

Explain what the student would see in each test tube and the tests that they should carry out to identify the gases produced.

Your answer should include word equations for the reactions that would take place.

The method used to extract a metal from its ore depends on the position of the metal in the reactivity series.

Aluminium is extracted from its ore by electrolysis.

Explain why this method is used to extract aluminium from its ore.

One step in the extraction of titanium metal involves the displacement reaction between titanium chloride, TiCl₄, and magnesium.

This equation can be simplified as

Explain why this displacement reaction can be described as a redox reaction.

The formula of the sulfate ion is SO²⁻₄.

Which of the following is the formula of titanium sulfate containing the Ti⁴⁺ ion?

Phytoextraction is an alternative biological method that can be used to extract metals from very low-grade ores.

Give one disadvantage of phytoextraction as a method of extraction of metals.

Copper is low down in the reactivity series and can be obtained from copper oxide.

Devise a simple method to obtain a sample of copper from copper oxide in the laboratory.

Some reactions are exothermic and some reactions are endothermic.

What does an exothermic reaction always give out?

In an experiment, a solid is mixed with a liquid. The temperature change of the mixture is measured.

Figure 3 shows the apparatus that is used.

Give the letter of the piece of apparatus, A, B, C or D, in Figure 3 that is used to measure the temperature.

Give the name of the piece of apparatus B shown in Figure 3.

The piece of apparatus labelled C is made from polystyrene.

State why polystyrene is a better material than glass for this piece of apparatus.

The results of the experiment are given in Figure 4.

Calculate the change in temperature.

Give a sign and a unit in your answer.

temperature change =_........

The solid used in this experiment contained only NH⁺₄ ions and NO^–₃ ions.

Give the formula and the name of the solid.

formula_........

name_........

A sample of potable water contains impurities.

Why is this sample of water potable even though it contains impurities?

Waste water can be used to produce drinking water. The processes used include sedimentation, filtration and chlorination.

What is sedimentation?

State why the waste water is filtered.

State the reason for chlorination.

Some salts can be added to waste water to remove impurities. In an experiment, different masses of salt A were added to 1000cm³ samples of waste water. The experiment was repeated with salt B. The percentages of impurities removed from the waste water are shown in Figure 3.

mass of salt in mg per 1000cm³ water

Figure 3

It was concluded that the best way to purify 1000cm³ of the waste water is to add 100 mg of salt B.

Use the information about salt A and salt B in Figure 3 to evaluate this conclusion.

Waste water may contain phosphate ions, PO₄^3-.

Aluminium ions react with phosphate ions to form aluminium phosphate.

Complete the ionic equation for the formation of aluminium phosphate in this reaction.

_........ + PO₄^3- _........

An ion of element X can be represented as

This ion of element X has 54 electrons.

Calculate the number of protons and the number of neutrons in this ion.

number of protons_........

number of neutrons_........

A sample of silicon contains isotopes.

State, in terms of subatomic particles, how atoms of these isotopes are the same.

This sample of silicon contains three isotopes.

92% of the atoms are silicon-28 5% of the atoms are silicon-29 3% of the atoms are silicon-30

Calculate the relative atomic mass of silicon in this sample.

relative atomic mass =_........

*(c) Figure 4 shows some properties of three substances, A, B and C.

Deduce, using the information in Figure 4, the structure and bonding of substances A, B and C, explaining their properties in terms of their structure and bonding.

This question is about potassium and zinc.

Which of the following temperatures is most likely to be the melting point of potassium?

Explain how the electronic configuration of an atom of potassium is related to its position in the periodic table.

Potassium reacts with oxygen to form potassium oxide.

Describe the test to show that a gas is oxygen.

Potassium oxide is ionic.

Write the electronic configurations for the ions in potassium oxide, K₂O.

potassium ion:_........

oxide ion:_........

Figure 4 shows two gas syringes connected by a glass tube.

Inside the glass tube there are some pieces of zinc. Zinc reacts with oxygen at a temperature of over 225 °C. Not all the oxygen reacts at once, the oxygen reacts only when in contact with the zinc.

Devise a plan to find the volume of oxygen contained in a known volume of air, using the apparatus shown in Figure 4.

Figure 6 shows the apparatus that can be used to electrolyse sodium sulfate solution using inert electrodes.

Hydrogen is produced at the negative electrode during electrolysis.

Describe the test to show the gas is hydrogen.

What is the name of gas X that forms at the positive electrode?

State what is meant by the term electrolysis.

The sodium sulfate solution was made by dissolving 28.4 g of sodium sulfate in water to make 250 cm³ of solution.

Calculate the concentration of this solution in g dm⁻³.

Give your answer to three significant figures.

concentration =_........ g dm

The ions present in sodium sulfate are

Write the formula of sodium sulfate using this information.

In Figure 6, the gases given off at the electrodes are collected in test-tubes. However, the actual volume of gases cannot be measured using these test-tubes.

Suggest what apparatus could be used in place of the test-tubes in Figure 6 to measure the volume of gases given off.

State what could be added into the circuit to show a current is flowing during electrolysis.

Figure 1 shows the apparatus that can be used to electrolyse sodium sulfate solution using inert electrodes.

Hydrogen is produced at the negative electrode during electrolysis.

Describe the test to show the gas is hydrogen.

What is the name of gas X that forms at the positive electrode?

State what is meant by the term electrolysis.

The sodium sulfate solution was made by dissolving 28.4 g of sodium sulfate in water to make 250 cm³ of solution.

Calculate the concentration of this solution in g dm⁻³.

Give your answer to three significant figures.

concentration =_........ g dm

An atom of potassium has atomic number 19 and mass number 39.

Give the electronic configuration of this potassium atom.

This potassium atom forms the ion K⁺.

Which row shows the number of protons and the number of neutrons in this potassium ion, K⁺?

Potassium and caesium are in the same group of the periodic table.

Explain, in terms of electrons, why potassium and caesium are in the same group.

Fluorine boils at –188C. There are forces between fluorine molecules.

Explain, in terms of these forces, why the boiling point of fluorine is low.

Potassium reacts with fluorine to form potassium fluoride. Potassium fluoride is a solid.

Complete the balanced equation for this reaction and add the state symbols.

_........ K (_........ ) + F₂(g) _........ KF (_........ )

What are the elements in group 1 of the periodic table called?

Figure 9 shows the melting points and boiling points of elements in group 7 of the periodic table.

Give, using Figure 9, the boiling point of bromine.

boiling point of bromine =_........ C

State which two elements from Figure 9 are solids at room temperature.

An atom of potassium has atomic number 19 and mass number 39.

Give the electronic configuration of this potassium atom.

This potassium atom forms the ion K⁺.

Which row shows the number of protons and the number of neutrons in this potassium ion, K⁺?

Potassium and caesium are in the same group of the periodic table.

Explain, in terms of electrons, why potassium and caesium are in the same group.

Fluorine boils at –188C. There are forces between fluorine molecules.

Explain, in terms of these forces, why the boiling point of fluorine is low.

Potassium reacts with fluorine to form potassium fluoride. Potassium fluoride is a solid.

Complete the balanced equation for this reaction and add the state symbols.

_........ K (_........ ) + F₂(g) _........ KF (_........ )

Air contains several gaseous elements.

Which of these shows the three most common gaseous elements in air, listed in order from the most common to the least common?

The density of a gas can be found using the equation

A student carried out an experiment to find the density of argon.

The mass of a stopper and flask, containing no gas, was known. The flask was completely filled with argon and its mass measured.

Figure 2 shows the results the student wrote down.

Use the results to calculate the density of argon in g cm^–3.

density of argon =_........ g cm^–3

The flask used for the experiment is shown in Figure 3. The flask holds 250.0 cm³ when filled up to the line.

There is an error in the volume the student has used in the calculation. This would give an incorrect value for the density of argon.

Identify this error and state what should be done to correct it.

error_........

what should be done to correct it_........

Four of the noble gases are argon, helium, krypton and neon.

Give these gases in order of increasing density.

Much of the carbon dioxide present in the Earth’s early atmosphere dissolved into the oceans.

This led to the formation of compounds including calcium carbonate, CaCO₃.

Some of the calcium carbonate reacted with magnesium ions to form dolomite, CaMg(CO₃)₂.

Complete the ionic equation for the reaction of calcium carbonate with magnesium ions.

_........ CaCO₃ +_........ CaMg(CO₃)₂ + Ca²⁺ dolomite

P and Q are both mixtures of gases. One has the same composition as the early atmosphere and the other has the same composition as the current atmosphere.

Tests are carried out on gas mixtures P and Q.

The test for carbon dioxide is to bubble the gas into limewater; if carbon dioxide is present calcium carbonate is formed.

The results of the tests are shown in Figure 4.

Explain, using the data in Figure 4, which gas mixture represents the early atmosphere.

(a) The reactivity of copper, magnesium and zinc was investigated. Each metal was placed separately in dilute hydrochloric acid. The amount of effervescence was observed.

The same mass of metal was used in each experiment. Which piece of apparatus should be used to find the mass of metal used?

State two variables, apart from the mass of the metals, that should be controlled in this investigation.

Magnesium produces the most vigorous effervescence. Copper does not produce any effervescence.

Give the reason why copper does not produce any effervescence.

The magnesium reacts with dilute hydrochloric acid to form magnesium chloride solution and hydrogen gas.

The equation for the reaction is

Mg(s) + 2HCl(aq) MgCl₂(_........ ) + H₂(_........ )

Fill in the missing state symbols in the spaces provided.

Potassium carbonate reacts with dilute sulfuric acid to form potassium sulfate.

Potassium sulfate contains potassium ions, K⁺, and sulfate ions, SO₄²⁻.

Write the formula of potassium sulfate.

Equal volumes of a solution of potassium carbonate were reacted separately with an excess of dilute sulfuric acid solution. Pure dry samples of potassium sulfate were obtained from the resulting solutions.

The experiment was repeated three times using the same conditions.

The masses of potassium sulfate obtained were

experiment 1 = 5.22 g experiment 2 = 5.24 g experiment 3 = 5.21 g

Calculate the mean mass of potassium sulfate obtained, giving your answer to two decimal places.

mean mass of potassium sulfate =_........ g

Metals are extracted from substances naturally occurring in the Earth’s crust.

Which of these metals is usually found uncombined in the Earth’s crust?

Zinc can be extracted by heating zinc oxide with carbon.

The products are zinc and carbon dioxide.

Write the word equation for this reaction.

In this reaction zinc oxide loses oxygen.

State the type of reaction taking place when an oxide loses oxygen.

Aluminium is extracted from aluminium oxide by electrolysis. Aluminium oxide is made up of ions.

The formula of aluminium oxide is Al₂O₃.

Give the number of ions in the formula Al₂O₃.

Complete the balanced equation for the overall reaction by putting numbers in the spaces.

2Al₂O_{3 ........} Al +_........ O₂

The environmental impact of a product is assessed in a life-cycle assessment.

The stages in this assessment are given below. They are not in the correct order.

A disposal of the product B manufacturing the product C obtaining and processing the raw materials D using the product

List the stages of the life-cycle assessment, using letters A, B, C, D, in the correct order from start to finish.

Aluminium can be obtained by recycling aluminium waste.

Give two advantages of obtaining aluminium by recycling aluminium waste rather than mining the raw material and extracting aluminium from that raw material.

In Figure 5, the letters A, E, G, J, X and Z show the positions of six elements in the periodic table.

These letters are not the symbols of the atoms of these elements.

Using the letters A, E, G, J, X and Z

give the letters of the two elements that are non-metals

give the letters of two elements in period 2

give the letter of an element that normally forms an ion with a charge of +1.

Element E has an atomic number of 5. In a sample of E there are two isotopes. One isotope has a mass number of 10 and the other isotope has a mass number of 11.

Explain, in terms of subatomic particles, what is meant by the term isotopes.

All atoms of element E in this sample contain

Element X has an atomic number of 18.

State the electronic configuration of an atom of element X.

In an experiment, 3.5 g of element A reacted with 4.0 g of element G to form a compound.

Calculate the empirical formula of this compound. (relative atomic masses: A = 7, G = 16)

You must show your working.

empirical formula of this compound =_........

An oxygen atom has six electrons in its outer shell.

A hydrogen atom has one electron in its outer shell.

Complete the dot and cross diagram of a molecule of water, H₂O.

Show outer shell electrons only.

In Figure 1, the letters A, E, G, J, X and Z show the positions of six elements in the periodic table.

These letters are not the symbols of the atoms of these elements.

Using the letters A, E, G, J, X and Z

give the letters of the two elements that are non-metals

give the letters of two elements in period 2

give the letter of an element that normally forms an ion with a charge of +1.

Element E has an atomic number of 5. In a sample of E there are two isotopes. One isotope has a mass number of 10 and the other isotope has a mass number of 11.

Explain, in terms of subatomic particles, what is meant by the term isotopes.

All atoms of element E in this sample contain

Element X has an atomic number of 18.

State the electronic configuration of an atom of element X.

In an experiment, 3.5 g of element A reacted with 4.0 g of element G to form a compound.

Calculate the empirical formula of this compound. (relative atomic masses: A = 7, G = 16)

You must show your working.

empirical formula of this compound =_........

An aluminium atom has the atomic number 13 and the mass number 27.

Which row shows the numbers of subatomic particles present in an

Magnesium burns in excess oxygen to form magnesium oxide. The balanced equation for this reaction is

Starting with 1.35 g of magnesium, calculate the maximum mass of magnesium oxide that could be formed in this reaction. (relative atomic masses: O = 16.0, Mg = 24.0)

You must show your working.

mass of magnesium oxide =_........ g

Chlorine reacts with hydrogen to form hydrogen chloride.

Write the balanced equation for this reaction.

*(d) Sodium chloride is an ionic compound, containing sodium ions, Na⁺, and chloride ions, Cl^–.

Figure 10 shows the electronic configuration of sodium and chlorine.

Explain how sodium and chlorine atoms form the ions in sodium chloride and how the ions are arranged in the solid sodium chloride.

You may wish to use diagrams in your answer.

An aluminium atom has the atomic number 13 and the mass number 27.

Which row shows the numbers of subatomic particles present in an

Magnesium burns in excess oxygen to form magnesium oxide. The balanced equation for this reaction is

Starting with 1.35 g of magnesium, calculate the maximum mass of magnesium oxide that could be formed in this reaction. (relative atomic masses: O = 16.0, Mg = 24.0)

You must show your working.

mass of magnesium oxide =_........ g

Chlorine reacts with hydrogen to form hydrogen chloride.

Write the balanced equation for this reaction.

Sodium reacts with chlorine to form sodium chloride.

The electronic configuration of the sodium atom is 2.8.1 and the electronic configuration of the chlorine atom is 2.8.7.

Give the electronic configurations of the ions formed.

Na⁺_........

Two compounds of barium are barium sulfide and barium chloride.

The hazard symbol shown in Figure 2 is on bottles containing barium metal.

State the meaning of this hazard symbol.

Give the names of the elements combined in barium sulfide.

Barium chloride is toxic.

Explain one safety precaution that should be taken when using barium chloride.

A beaker of barium chloride solution and a beaker of dilute sulfuric acid were placed on a balance, as shown in Figure 3.

The total mass reading on the balance was 25.7 g.

The dilute sulfuric acid was poured into the barium chloride solution and the beaker replaced on the balance, as shown in Figure 4.

Figure 4

The mixture formed contained a white precipitate.

State the total mass reading on the balance after the reaction.

Give the name of the white precipitate formed by the reaction of barium chloride solution with dilute sulfuric acid.

Solid sodium chloride is dissolved in water.

The sodium chloride solution is electrolysed in the apparatus shown in Figure 5.

State why sodium chloride solution, rather than solid sodium chloride, must be used in this experiment.

The formulae of the ions present in the sodium chloride solution are

Circle the ions that would be attracted to the anode.

Molten lead bromide can be electrolysed to form molten lead and bromine gas.

Explain how a student could modify the apparatus shown in Figure 5 to carry out this electrolysis.

State two characteristic properties of metals.

property 1_........

property 2_........

Acids are used to make salts.

Give the name of the acid used to make chlorides.

Salts of metals can be prepared by reacting the metal with an acid to produce the salt and hydrogen.

Describe the test to show that the gas is hydrogen.

Nickel is a metal.

Explain how the structure of a nickel atom, Ni, changes when it forms a nickel ion, Ni²⁺

A nickel sulfate solution is made by dissolving 23.5 g of nickel sulfate to make 250 cm³ of solution.

Calculate the concentration of the solution in g dm^–3.

concentration =_........ g dm

Excess solid nickel carbonate is added to dilute sulfuric acid in a beaker.

nickel sulfuric nickel carbon

Nickel sulfate is formed in solution.

Describe how a sample of pure, dry nickel sulfate crystals can be obtained from the mixture of nickel sulfate solution and excess solid nickel carbonate in the beaker.

(a) Salts of metals can be prepared by reacting the metal with an acid to produce the salt and hydrogen.

Describe the test to show the gas is hydrogen.

Nickel is a metal.

Explain how the structure of a nickel atom, Ni, changes when it forms a nickel ion, Ni²⁺.

A nickel sulfate solution is made by dissolving 23.5 g of nickel sulfate to make 250 cm³ of solution.

Calculate the concentration of the solution in g dm⁻³.

concentration =_........ g dm