Define reactivity series .

The reactivity series is an ordered list of metals (and some non-metals) arranged from most to least reactive. The reactivity of a metal is related to its tendency to form positive ions by losing electrons.

Place these metals in order from most to least reactive: copper, calcium, magnesium, zinc, potassium, iron

Most to least reactive: Potassium Calcium Magnesium Zinc Iron Copper

True or False? A more reactive metal can displace a less reactive metal from a compound.

True. This is called a displacement reaction . The more reactive metal donates electrons to the metal ion in the compound, reducing it to the metal. For example, magnesium displaces copper from copper sulfate solution.

When magnesium is added to copper sulfate solution, the blue colour .......... because .......... sulfate forms. The more reactive metal .......... the less reactive one.

When magnesium is added to copper sulfate solution, the blue colour fades because magnesium sulfate forms. The more reactive metal displaces the less reactive one.

Why do metals above hydrogen in the reactivity series react with dilute acids but metals below hydrogen do not?

Metals above hydrogen in the reactivity series are reactive enough to displace hydrogen from the acid, forming a salt and hydrogen gas . Metals below hydrogen are not reactive enough to displace it and so do not react with dilute acids.

True or False? Carbon and hydrogen appear in the reactivity series because they are metals.

False. Carbon and hydrogen are non-metals but are included in the reactivity series because they are useful for extracting metals from their ores and for understanding which metals react with water and acids.

What products are formed when a metal above hydrogen reacts with cold water ?

When a metal above hydrogen reacts with cold water, it produces a metal hydroxide and hydrogen gas: metal + water → metal hydroxide + hydrogen For example: Ca + 2H 2 O → Ca(OH) 2 + H 2

In the thermite reaction , why does aluminium displace iron from iron(III) oxide?

Aluminium is higher in the reactivity series than iron, so it is more reactive. The more reactive metal (aluminium) displaces the less reactive metal (iron) from the oxide, producing iron and aluminium oxide .

Define electrolysis .

Electrolysis is the process by which an electric current is passed through a molten or dissolved ionic compound (the electrolyte ), causing it to decompose into its elements.

An electrolyte is a liquid or solution that can conduct electricity during electrolysis. It must contain free-moving ions , which means it must be either molten or dissolved in water.

In electrolysis, which electrode is the anode and which is the cathode ?

The anode is the positive (+) electrode. The cathode is the negative (−) electrode. Positive ions (cations) move towards the cathode; negative ions (anions) move towards the anode.

True or False? Solid ionic compounds can conduct electricity and undergo electrolysis.

False. In the solid state , ions are in fixed positions and cannot move, so solid ionic compounds cannot conduct electricity. Ions must be free to move — either in the molten state or dissolved in solution — for electrolysis to occur.

In the electrolysis of molten lead(II) bromide, .......... is produced at the cathode and .......... gas is produced at the anode.

In the electrolysis of molten lead(II) bromide, lead is produced at the cathode and bromine gas is produced at the anode.

Why are inert electrodes (graphite or platinum) used in electrolysis?

Inert electrodes do not react with the electrolyte or the products of electrolysis. If reactive electrodes were used, they could dissolve or produce unwanted side reactions, making it impossible to identify the true products of electrolysis.

True or False? In the electrolysis of a binary molten ionic compound, the metal is always produced at the anode.

False. In the electrolysis of a binary molten ionic compound, the metal (positive ion) is produced at the cathode (negative electrode). The non-metal (negative ion) is produced at the anode (positive electrode).

What would be observed at each electrode when molten lead(II) bromide is electrolysed?

At the cathode : grey lead metal is deposited. At the anode : brown bromine gas is produced, seen as bubbling.

In the electrolysis of aqueous solutions, what additional ions are always present besides those from the dissolved compound?

Water dissociates to give H + and OH - ions: H 2 O ⇌ H + + OH - These ions compete with the ions from the dissolved compound and affect the products of electrolysis.

Define discharge (electrolysis).

An ion is discharged during electrolysis when it gains or loses electrons at an electrode to form a neutral atom or molecule. The less reactive ion is preferentially discharged.

True or False? In the electrolysis of copper sulfate solution, copper is deposited at the cathode because copper is below hydrogen in the reactivity series.

True. At the cathode, both Cu 2+ and H + are present. Because copper is below hydrogen in the reactivity series , the Cu 2+ ion is less reactive and is preferentially discharged , depositing copper metal.

At the anode in electrolysis, if .......... ions are present, .......... gas is produced. If no halide ions are present, .......... gas is produced instead.

At the anode in electrolysis, if halide ions are present, halogen gas is produced. If no halide ions are present, oxygen gas is produced instead.

What is produced at each electrode in the electrolysis of sodium chloride solution ?

Cathode: hydrogen gas (sodium is above hydrogen in the reactivity series, so H + is discharged instead) Anode: chlorine gas (Cl − is a halide ion and is preferentially discharged over OH − )

True or False? In the electrolysis of magnesium iodide solution, magnesium metal is deposited at the cathode.

False. Magnesium is above hydrogen in the reactivity series , so H + ions from water are discharged at the cathode instead of Mg 2+ ions. Hydrogen gas is produced at the cathode, not magnesium metal. At the anode, iodine is produced because I - is a halide ion.

Predict the products at both electrodes in the electrolysis of copper sulfate solution .

Cathode: copper metal is deposited (Cu 2+ is below H + in reactivity, so Cu 2+ is discharged) Anode: oxygen gas (no halide ions present, so OH - is discharged to form O 2 and water)

In Required Practical 21, what is the dependent variable ?

The dependent variable is the products observed at each electrode (gas produced or solid deposited).

In Required Practical 21, how would you confirm the gas collected at the cathode is hydrogen?

Hold a burning splint at the mouth of the test tube containing the gas. If the gas is hydrogen , it will burn rapidly with a loud squeaky pop .

True or False? In Required Practical 21, when copper chloride solution is electrolysed, a pink/orange solid is deposited at the anode.

False. The pink/orange copper solid is deposited at the cathode (negative electrode), not the anode. At the anode, chlorine gas is produced from the discharge of Cl - ions.

In Required Practical 21, how would you confirm the gas collected at the anode is chlorine?

Hold damp blue litmus paper near the gas. If the gas is chlorine , the litmus paper turns red and is then bleached white .

In Required Practical 21, when sodium chloride solution is electrolysed, .......... is produced at the cathode and .......... is produced at the anode.

In Required Practical 21, when sodium chloride solution is electrolysed, hydrogen is produced at the cathode and chlorine is produced at the anode.

Why are carbon rod electrodes used in Required Practical 21 rather than copper electrodes?

Carbon rod electrodes are inert — they do not react with the electrolyte or the products. Copper electrodes would dissolve or react during electrolysis, interfering with the results and making it impossible to observe the true products.

True or False? When sodium nitrate solution is electrolysed in Required Practical 21, oxygen is produced at the anode because no halide ions are present.

True. With no halide ions present, OH - ions from water are discharged at the anode, producing oxygen gas. A glowing splint relights in the collected gas, confirming it is oxygen.

An electrode is a solid conductor through which the electric current enters and leaves the electrolyte during electrolysis. The positive electrode is called the anode and the negative electrode is called the cathode .

Define squeaky pop test .

The squeaky pop test is the test for hydrogen gas. A burning splint is held at the mouth of a test tube of the gas. Hydrogen burns rapidly with a loud "squeaky pop" sound.

Define glowing splint test .

The glowing splint test is the test for oxygen gas. A glowing (not burning) splint is inserted into a test tube of the gas. In the presence of oxygen, the splint relights .

True or False? Damp red litmus paper turns blue and is then bleached white in the presence of chlorine gas.

False. Damp blue litmus paper (not red) is used to test for chlorine . It first turns red (because chlorine dissolves in water to form an acid) and is then bleached white .

State the test and positive result for oxygen gas.

Test: insert a glowing splint into a test tube of the gas. Positive result: the glowing splint relights .

To test for hydrogen , hold a .......... splint at the mouth of the test tube. A positive result is a .......... sound. To test for chlorine , place damp blue .......... paper into the gas; it turns red and is bleached ........... .

To test for hydrogen , hold a burning splint at the mouth of the test tube. A positive result is a squeaky pop sound. To test for chlorine , place damp blue litmus paper into the gas; it turns red and is bleached white .

True or False? Chlorine gas can be identified by its smell alone in a school laboratory.

False. Although chlorine has a characteristic sharp smell, smell alone is not an acceptable identification test . The correct test is damp blue litmus paper , which turns red and is bleached white . Chlorine should always be handled in a fume cupboard due to its toxicity.

Why must the burning splint be held at the mouth of the test tube, not inserted deeply, when testing for hydrogen?

Hydrogen needs oxygen from the air to burn. Inserting the splint deep into the tube would cut off the air supply, preventing combustion. Holding it at the mouth allows the gas to mix with air and burn with the characteristic squeaky pop .

Define oxidation (electron transfer). (Higher Tier Only)

Oxidation is the loss of electrons. A species that loses electrons during a reaction is said to have been oxidised. Remembered using OIL (Oxidation Is Loss).

Define reduction (electron transfer). (Higher Tier Only)

Reduction is the gain of electrons. A species that gains electrons during a reaction is said to have been reduced. Remembered using RIG (Reduction Is Gain).

True or False? In the reaction Fe + Cu 2+ → Fe 2+ + Cu, iron is reduced. (Higher Tier Only)

False. Iron loses electrons (Fe → Fe 2+ + 2e - ), so it is oxidised . Copper gains electrons (Cu 2+ + 2e - → Cu), so copper is reduced . This is a redox reaction.

What is a redox reaction ? (Higher Tier Only)

A redox reaction is one in which oxidation and reduction occur simultaneously. One species loses electrons (is oxidised) while another gains those electrons (is reduced).

In electrolysis, .......... takes place at the cathode (ions .......... electrons), and .......... takes place at the anode (ions .......... electrons). (Higher Tier Only)

In electrolysis, reduction takes place at the cathode (ions gain electrons), and oxidation takes place at the anode (ions lose electrons).

In the displacement reaction Zn + Cu 2+ → Zn 2+ + Cu, write the half equations for oxidation and reduction. (Higher Tier Only)

Oxidation (zinc loses electrons): Zn → Zn 2+ + 2e - Reduction (copper ions gain electrons): Cu 2+ + 2e - → Cu

What are spectator ions and why are they excluded from ionic equations? (Higher Tier Only)

Spectator ions are ions that appear unchanged on both sides of a full equation — they do not participate in the reaction. They are excluded from ionic equations to show only the species that actually change, making the chemistry clearer.

GCSEScienceAQACombined Science: SynergyPhysical SciencesFlashcardsMovement & InteractionsAtoms into Ions & Ions into Atoms

Atoms into Ions & Ions into Atoms (AQA GCSE Combined Science: Synergy: Physical Sciences): Flashcards

Exam code: 8465

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FrontA Reactivity Series For Metals
Define reactivity series.
FrontA Reactivity Series For Metals
Place these metals in order from most to least reactive: copper, calcium, magnesium, zinc, potassium, iron
BackA Reactivity Series For Metals
Most to least reactive:
Potassium
Calcium
Magnesium
Zinc
Iron
Copper

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Cards in this collection (45)

Define reactivity series.
The reactivity series is an ordered list of metals (and some non-metals) arranged from most to least reactive. The reactivity of a metal is related to its tendency to form positive ions by losing electrons.
Place these metals in order from most to least reactive: copper, calcium, magnesium, zinc, potassium, iron
Most to least reactive:
1. Potassium
2. Calcium
3. Magnesium
4. Zinc
5. Iron
6. Copper
True or False?
A more reactive metal can displace a less reactive metal from a compound.
True.
This is called a displacement reaction. The more reactive metal donates electrons to the metal ion in the compound, reducing it to the metal. For example, magnesium displaces copper from copper sulfate solution.
When magnesium is added to copper sulfate solution, the blue colour .......... because .......... sulfate forms. The more reactive metal .......... the less reactive one.
When magnesium is added to copper sulfate solution, the blue colour fades because magnesium sulfate forms. The more reactive metal displaces the less reactive one.
Why do metals above hydrogen in the reactivity series react with dilute acids but metals below hydrogen do not?
Metals above hydrogen in the reactivity series are reactive enough to displace hydrogen from the acid, forming a salt and hydrogen gas. Metals below hydrogen are not reactive enough to displace it and so do not react with dilute acids.
True or False?
Carbon and hydrogen appear in the reactivity series because they are metals.
False.
Carbon and hydrogen are non-metals but are included in the reactivity series because they are useful for extracting metals from their ores and for understanding which metals react with water and acids.
What products are formed when a metal above hydrogen reacts with cold water?
When a metal above hydrogen reacts with cold water, it produces a metal hydroxide and hydrogen gas:
metal + water → metal hydroxide + hydrogen
For example: Ca + 2H₂O → Ca(OH)₂ + H₂
In the thermite reaction, why does aluminium displace iron from iron(III) oxide?
Aluminium is higher in the reactivity series than iron, so it is more reactive. The more reactive metal (aluminium) displaces the less reactive metal (iron) from the oxide, producing iron and aluminium oxide.
Define electrolysis.
Electrolysis is the process by which an electric current is passed through a molten or dissolved ionic compound (the electrolyte), causing it to decompose into its elements.
Define electrolyte.
An electrolyte is a liquid or solution that can conduct electricity during electrolysis. It must contain free-moving ions, which means it must be either molten or dissolved in water.
In electrolysis, which electrode is the anode and which is the cathode?
The anode is the positive (+) electrode.
The cathode is the negative (−) electrode.
Positive ions (cations) move towards the cathode; negative ions (anions) move towards the anode.
True or False?
Solid ionic compounds can conduct electricity and undergo electrolysis.
False.
In the solid state, ions are in fixed positions and cannot move, so solid ionic compounds cannot conduct electricity. Ions must be free to move — either in the molten state or dissolved in solution — for electrolysis to occur.
In the electrolysis of molten lead(II) bromide, .......... is produced at the cathode and .......... gas is produced at the anode.
In the electrolysis of molten lead(II) bromide, lead is produced at the cathode and bromine gas is produced at the anode.
Why are inert electrodes (graphite or platinum) used in electrolysis?
Inert electrodes do not react with the electrolyte or the products of electrolysis. If reactive electrodes were used, they could dissolve or produce unwanted side reactions, making it impossible to identify the true products of electrolysis.
True or False?
In the electrolysis of a binary molten ionic compound, the metal is always produced at the anode.
False.
In the electrolysis of a binary molten ionic compound, the metal (positive ion) is produced at the cathode (negative electrode). The non-metal (negative ion) is produced at the anode (positive electrode).
What would be observed at each electrode when molten lead(II) bromide is electrolysed?
At the cathode: grey lead metal is deposited.
At the anode: brown bromine gas is produced, seen as bubbling.
In the electrolysis of aqueous solutions, what additional ions are always present besides those from the dissolved compound?
Water dissociates to give H⁺ and OH^- ions:
H₂O ⇌ H⁺ + OH^-
These ions compete with the ions from the dissolved compound and affect the products of electrolysis.
Define discharge (electrolysis).
An ion is discharged during electrolysis when it gains or loses electrons at an electrode to form a neutral atom or molecule. The less reactive ion is preferentially discharged.
True or False?
In the electrolysis of copper sulfate solution, copper is deposited at the cathode because copper is below hydrogen in the reactivity series.
True.
At the cathode, both Cu²⁺ and H⁺ are present. Because copper is below hydrogen in the reactivity series, the Cu²⁺ ion is less reactive and is preferentially discharged, depositing copper metal.
At the anode in electrolysis, if .......... ions are present, .......... gas is produced. If no halide ions are present, .......... gas is produced instead.
At the anode in electrolysis, if halide ions are present, halogen gas is produced. If no halide ions are present, oxygen gas is produced instead.
What is produced at each electrode in the electrolysis of sodium chloride solution?
Cathode: hydrogen gas (sodium is above hydrogen in the reactivity series, so H⁺ is discharged instead)
Anode: chlorine gas (Cl⁻ is a halide ion and is preferentially discharged over OH⁻)
True or False?
In the electrolysis of magnesium iodide solution, magnesium metal is deposited at the cathode.
False.
Magnesium is above hydrogen in the reactivity series, so H⁺ ions from water are discharged at the cathode instead of Mg²⁺ ions. Hydrogen gas is produced at the cathode, not magnesium metal. At the anode, iodine is produced because I^- is a halide ion.
Predict the products at both electrodes in the electrolysis of copper sulfate solution.
Cathode: copper metal is deposited (Cu²⁺ is below H⁺ in reactivity, so Cu²⁺ is discharged)
Anode: oxygen gas (no halide ions present, so OH^- is discharged to form O₂ and water)
In Required Practical 21, what is the dependent variable?
The dependent variable is the products observed at each electrode (gas produced or solid deposited).
In Required Practical 21, how would you confirm the gas collected at the cathode is hydrogen?
Hold a burning splint at the mouth of the test tube containing the gas. If the gas is hydrogen, it will burn rapidly with a loud squeaky pop.
True or False?
In Required Practical 21, when copper chloride solution is electrolysed, a pink/orange solid is deposited at the anode.
False.
The pink/orange copper solid is deposited at the cathode (negative electrode), not the anode. At the anode, chlorine gas is produced from the discharge of Cl^- ions.
In Required Practical 21, how would you confirm the gas collected at the anode is chlorine?
Hold damp blue litmus paper near the gas. If the gas is chlorine, the litmus paper turns red and is then bleached white.
In Required Practical 21, when sodium chloride solution is electrolysed, .......... is produced at the cathode and .......... is produced at the anode.
In Required Practical 21, when sodium chloride solution is electrolysed, hydrogen is produced at the cathode and chlorine is produced at the anode.
Why are carbon rod electrodes used in Required Practical 21 rather than copper electrodes?
Carbon rod electrodes are inert — they do not react with the electrolyte or the products. Copper electrodes would dissolve or react during electrolysis, interfering with the results and making it impossible to observe the true products.
True or False?
When sodium nitrate solution is electrolysed in Required Practical 21, oxygen is produced at the anode because no halide ions are present.
True.
With no halide ions present, OH^- ions from water are discharged at the anode, producing oxygen gas. A glowing splint relights in the collected gas, confirming it is oxygen.
Define electrode.
An electrode is a solid conductor through which the electric current enters and leaves the electrolyte during electrolysis. The positive electrode is called the anode and the negative electrode is called the cathode.
Define squeaky pop test.
The squeaky pop test is the test for hydrogen gas. A burning splint is held at the mouth of a test tube of the gas. Hydrogen burns rapidly with a loud "squeaky pop" sound.
Define glowing splint test.
The glowing splint test is the test for oxygen gas. A glowing (not burning) splint is inserted into a test tube of the gas. In the presence of oxygen, the splint relights.
True or False?
Damp red litmus paper turns blue and is then bleached white in the presence of chlorine gas.
False.
Damp blue litmus paper (not red) is used to test for chlorine. It first turns red (because chlorine dissolves in water to form an acid) and is then bleached white.
State the test and positive result for oxygen gas.
Test: insert a glowing splint into a test tube of the gas.
Positive result: the glowing splint relights.
To test for hydrogen, hold a .......... splint at the mouth of the test tube. A positive result is a .......... sound. To test for chlorine, place damp blue .......... paper into the gas; it turns red and is bleached ............
To test for hydrogen, hold a burning splint at the mouth of the test tube. A positive result is a squeaky pop sound. To test for chlorine, place damp blue litmus paper into the gas; it turns red and is bleached white.
True or False?
Chlorine gas can be identified by its smell alone in a school laboratory.
False.
Although chlorine has a characteristic sharp smell, smell alone is not an acceptable identification test. The correct test is damp blue litmus paper, which turns red and is bleached white. Chlorine should always be handled in a fume cupboard due to its toxicity.
Why must the burning splint be held at the mouth of the test tube, not inserted deeply, when testing for hydrogen?
Hydrogen needs oxygen from the air to burn. Inserting the splint deep into the tube would cut off the air supply, preventing combustion. Holding it at the mouth allows the gas to mix with air and burn with the characteristic squeaky pop.
Define oxidation (electron transfer).
(Higher Tier Only)
Oxidation is the loss of electrons. A species that loses electrons during a reaction is said to have been oxidised. Remembered using OIL (Oxidation Is Loss).
Define reduction (electron transfer).
(Higher Tier Only)
Reduction is the gain of electrons. A species that gains electrons during a reaction is said to have been reduced. Remembered using RIG (Reduction Is Gain).
True or False?
In the reaction Fe + Cu²⁺ → Fe²⁺ + Cu, iron is reduced.
(Higher Tier Only)
False.
Iron loses electrons (Fe → Fe²⁺ + 2e^-), so it is oxidised. Copper gains electrons (Cu²⁺ + 2e^- → Cu), so copper is reduced. This is a redox reaction.
What is a redox reaction?
(Higher Tier Only)
A redox reaction is one in which oxidation and reduction occur simultaneously. One species loses electrons (is oxidised) while another gains those electrons (is reduced).
In electrolysis, .......... takes place at the cathode (ions .......... electrons), and .......... takes place at the anode (ions .......... electrons).
(Higher Tier Only)
In electrolysis, reduction takes place at the cathode (ions gain electrons), and oxidation takes place at the anode (ions lose electrons).
In the displacement reaction Zn + Cu²⁺ → Zn²⁺ + Cu, write the half equations for oxidation and reduction.
(Higher Tier Only)
Oxidation (zinc loses electrons):
Zn → Zn²⁺ + 2e^-
Reduction (copper ions gain electrons):
Cu²⁺ + 2e^- → Cu
What are spectator ions and why are they excluded from ionic equations?
(Higher Tier Only)
Spectator ions are ions that appear unchanged on both sides of a full equation — they do not participate in the reaction. They are excluded from ionic equations to show only the species that actually change, making the chemistry clearer.

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