Ionic bonding & ionic compounds

This question is about metals and metal compounds.

A teacher demonstrated the reaction of copper with silver nitrate.

Figure 6 shows the apparatus:

at the start

after a few minutes.

The word equation for the reaction is:

copper + silver nitrate copper nitrate + silver

Silver ions are reduced to silver atoms in the reaction.

What is meant by ‘reduced’ in this reaction?

Complete the ionic equation for the reaction between copper and silver nitrate solution.

You should balance the equation.

Copper nitrate is made up of Cu²⁺ ions and NO₃⁻ ions.

What is the formula of copper nitrate?

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CuNO₃

Cu(NO₃)₂

Cu₂NO₃

Cu₂(NO₃)₃

Figure 7 shows the order of reactivity for three metals.

Table 2 shows the colours of three metal nitrate solutions.

The teacher added an excess of each metal to each metal nitrate solution.

Complete Table 3 to show the colours of the resultant solutions.

Copper is a good conductor of electricity.

Explain how copper conducts electricity.

Pure copper is too soft for many uses.

Copper is mixed with other metals to make copper alloys.

Explain why copper alloys are harder than pure copper.

The elements in Group 1 of the periodic table are called the alkali metals.

Lithium reacts with chlorine to produce lithium chloride.

Figure 11 shows the reaction profile for the reaction between lithium and chlorine.

What do labels A, B and C on Figure 11 represent?

What type of reaction does the reaction profile in Figure 11 represent?

Describe what happens when a lithium atom reacts with a chlorine atom.

Answer in terms of electrons.

Explain the trend in the reactivity of the Group 1 metals.

This question is about the elements magnesium, oxygen and lithium.

What is the type of bonding in magnesium?

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Covalent

Ionic

Metallic

What is the type of bonding in oxygen?

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Covalent

Ionic

Metallic

Magnesium atoms react with oxygen atoms to produce magnesium oxide.

Magnesium oxide contains magnesium ions and oxide ions.

Figure 8 shows the electronic structure of the atoms and the ions.

Only the outer shell electrons are shown.

Describe what happens when a magnesium atom reacts with an oxygen atom to produce a magnesium ion and an oxide ion.

Answer in terms of electrons.

Lithium is an element in Group 1 of the periodic table.

Figure 9 shows a piece of lithium stored in oil.

Suggest why lithium is stored in oil.

A teacher reacted 0.5 g of lithium with oxygen.

The teacher measured the mass of lithium oxide produced.

The teacher repeated the experiment with different masses of lithium.

Table 2 shows the results.

Describe the relationship between the mass of lithium reacted and the mass of lithium oxide produced.

Complete Figure 10.

You should:

label the x-axis

plot the data from Table 2

draw a line of best fit.

The teacher did the experiment four times using 0.25 g of lithium.

Table 3 shows the results.

Calculate mean value X in Table 3.

Magnesium reacts with oxygen to form magnesium oxide.

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

A student reacted different masses of magnesium with oxygen.

The student determined the mass of magnesium oxide produced.

Table 3 shows the results.

Complete Figure 6.

You should:

use a suitable scale for the y-axis

plot the data from Table 3.

The first point has been plotted for you.

The student’s results cannot be used to show that the method gives precise measurements.

Give one reason why.

This question is about acids and salts.

Nitric acid is a strong acid.

A solution of nitric acid can be dilute.

Explain how nitric acid can be both strong and dilute.

The pH value of a solution of nitric acid increases by 1.

How does the hydrogen ion concentration of the solution change?

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Decreases by a factor of 10

Decreases by a factor of 100

Increases by a factor of 10

Increases by a factor of 100

Question 8 continues in the next page

A student reacted nitric acid with excess calcium carbonate.

The word equation for the reaction is:

calcium carbonate + nitric acid calcium nitrate + water + carbon dioxide

This is the method used.

1. Measure 100 cm³ of nitric acid into a beaker.

2. Add calcium carbonate powder to the nitric acid.

3. Stir the mixture.

4. Repeat steps 2 and 3 until the calcium carbonate is in excess.

5. Filter the mixture.

Describe the additional steps that should be included in the method to determine the mass of calcium carbonate that reacted.

The formula of nitric acid is HNO₃

Which expression gives the percentage (%) by mass of oxygen in HNO₃?

Relative atomic mass (A_r): O = 16

Relative formula mass (M_r): HNO₃ = 63

Tick (✓) one box.

What is the formula of calcium nitrate?

Use the periodic table.

Tick (✓) one box.

CaNO₃

Ca(NO₃)₂

Ca₂NO₃

Ca₂(NO₃)₃

Question 8 continues in the next page

Magnesium chloride is a salt.

Calculate the number of magnesium ions in 47.5 g of magnesium chloride (MgCl₂).

Relative atomic masses (A_r): Mg = 24 Cl = 35.5

Avogadro constant = 6.02 × 10²³ per mole

This question is about metal extraction and recycling.

Most metals are found in the Earth as metal compounds.

Why is gold found in the Earth as the metal itself?

How is aluminium extracted from aluminium compounds?

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By displacement

By electrolysis

By reduction with carbon

Iron is extracted from iron oxide.

An oxide ion is an oxygen atom that has gained two electrons.

What is the formula of an oxide ion?

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O₂ O²⁻ O²⁺

Iron oxide is heated with carbon to produce iron and carbon dioxide.

The word equation for the reaction is:

Which substance is oxidised in the reaction?

Iron is used to make steel.

Scrap steel can be recycled.

Give two environmental advantages of recycling scrap steel instead of making new steel from iron.

Table 3 shows information about scrap steel in one year.

Calculate the percentage (%) of scrap steel that was recycled in one year.

Figure 5 shows metal food and drink cans.

The metal cans are made from steel or aluminium.

Which property of steel means that steel can be separated from aluminium at a recycling centre?

This question is about reactions of metals.

A student investigated the reactivity of three metals.

Figure 1 shows the order of reactivity of the three metals.

The student added each metal to three different metal sulfate solutions.

Table 1 shows some of the results.

A more reactive metal displaces a less reactive metal from a compound.

Complete Table 1.

Use: where a reaction occurs where there is no reaction.

Use Figure 1.

What type of solution is formed when potassium reacts with water?

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Acidic

Alkaline

Neutral

Which gas is produced when potassium reacts with water?

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Carbon dioxide

Hydrogen

Oxygen

Give one observation seen when potassium is added to water.

Sodium is above potassium in Group 1 of the periodic table.

How does the reactivity of sodium compare with the reactivity of potassium?

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Sodium is less reactive than potassium.

Sodium has the same reactivity as potassium.

Sodium is more reactive than potassium.

Figure 3 shows the electronic structure of two different atoms.

A sodium atom forms a Na + ion.

Which ion does a magnesium atom form?

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Mg⁺ Mg⁻ Mg²⁺ Mg²⁻

This question is about ammonium chloride.

Ammonium chloride (NH₄Cl) decomposes to produce ammonia (NH₃) and hydrogen chloride (HC l).

The reaction is reversible.

The equation for the reaction is:

What is the state of hydrogen chloride in this reaction?

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Aqueous

Gas

Liquid

Solid

How does the equation show that the reaction is reversible?

What is the total number of atoms in the formula NH₄C඀?

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3 4 5 6

When does a reversible reaction reach dynamic equilibrium?

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When the forward reaction is slower than the reverse reaction.

When the forward reaction and the reverse reaction have the same rate.

When the forward reaction is faster than the reverse reaction.

How must the apparatus for the reaction be designed so that dynamic equilibrium can be reached?

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So all of the substances can escape.

So none of the substances can escape.

So only ammonia and hydrogen chloride can escape.

Figure 7 represents the electronic structure of a chlorine atom (C ඀).

Which diagram represents the electronic structure of a chloride ion (C ඀ −)?

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Ammonia has the formula NH₃

Calculate the percentage (%) by mass of nitrogen (N) in NH₃

Relative atomic mass (A_r): N = 14

Relative formula mass (M_r): NH₃ = 17

Give your answer to 2 significant figures.

Figure 8 represents ammonia.

What does ‘ ’ represent in Figure 8?

What type of particle is ammonia?

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Atom

Ion

Molecule 11

This question is about reactions of metals.

A piece of magnesium reacts with dilute hydrochloric acid.

Magnesium chloride solution and a gas are produced.

Which gas is produced?

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Chlorine

Hydrogen

Oxygen

Give two observations seen during the reaction.

Magnesium chloride is formed from Mg²⁺ ions and Cl^‒ ions.

What is the formula of magnesium chloride?

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MgCl MgCl₂ Mg₂Cl Mg₂Cl₂

Calcium is in the same group as magnesium in the periodic table.

What is the symbol for a calcium ion?

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Ca⁺ Ca^‒ Ca²⁺ Ca^2‒

Figure 2 shows a cube of calcium.

How would you calculate the total surface area of this cube?

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Total surface area = 2 × 2 × 2

Total surface area = 2 × 2 × 4

Total surface area = 2 × 2 × 6

Total surface area = 2 × 4 × 6

A teacher investigated the reaction between calcium and water.

The teacher used the same mass of three different forms of calcium.

The different forms of calcium were: powder small lumps large lumps.

The teacher measured the time for each reaction to be complete.

What is the independent variable in the investigation?

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Form of calcium

Mass of calcium

Time for reaction to be complete

Which form of calcium will react the fastest?

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Powder

Small lumps

Large lumps

Which is the best way to display the results for the three different forms of calcium?

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Bar chart

Line graph

Pie chart

This question is about structure and bonding.

Figure 10 represents the electronic structure of an atom of an element.

Name the element in Figure 10.

Give one reason for your answer.

Use the periodic table.

Sodium reacts with fluorine to produce sodium fluoride.

Sodium fluoride is an ionic compound.

An atom of sodium and an atom of fluorine react to form a sodium ion and a fluoride ion.

Complete the dot and cross diagram for the sodium ion and the fluoride ion.

Show the charges on the ions.

Figure 11 represents the structure of sodium fluoride.

Describe how sodium ions and fluoride ions are held together in sodium fluoride.

What is a property of sodium fluoride?

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Conducts electricity when solid

High melting point

Low boiling point

This question is about structure and bonding.

Figure 1 represents the electronic structure of an atom of an element.

Name the element in Figure 1.

Give one reason for your answer.

Use the periodic table.

Sodium reacts with fluorine to produce sodium fluoride.

Sodium fluoride is an ionic compound.

An atom of sodium and an atom of fluorine react to form a sodium ion and a fluoride ion.

Complete the dot and cross diagram for the sodium ion and the fluoride ion.

Show the charges on the ions.

Figure 2 represents the structure of sodium fluoride.

Describe how sodium ions and fluoride ions are held together in sodium fluoride.

What is a property of sodium fluoride?

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Conducts electricity when solid

High melting point

Low boiling point

This question is about elements.

Figure 1 shows the chemical symbols of five elements in the periodic table.

Which element is a noble gas?

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Which element forms fullerenes?

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Which two elements have atoms with the same number of electrons in their outer shell?

Use Figure 1.

Argon is very unreactive.

Figure 2 represents the electronic structure of an argon atom.

How does the electronic structure show that argon is unreactive?

Figure 3 shows some of the elements in Group 7 of the periodic table.

Chlorine gas consists of molecules.

What is the formula of a chlorine gas molecule?

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Which Group 7 element is the most reactive?

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Lithium atoms react with bromine atoms to produce lithium bromide.

Lithium bromide contains lithium ions and bromide ions.

Figure 4 shows the electronic structure of the atoms and ions.

The symbols (o) and (x) represent electrons.

Only the outer shell electrons are shown.

Describe what happens when a lithium atom reacts with a bromine atom to produce a lithium ion and a bromide ion.

This question is about halogens.

Bromine reacts with sodium to produce sodium bromide.

Describe the structure of and bonding in sodium bromide.

The equation for the reaction is:

1 g of bromine reacts with sodium.

Calculate the number of bromine molecules in 1 g of bromine.

1 mole of bromine contains 6.02 × 10²³ bromine molecules.

Relative formula mass (M_r) of bromine = 160

Table 5 shows the boiling points of some halogens.

Explain the trend in the boiling points of the halogens.