S3 - Metals Flashcards
What structure do metals have?
A giant structure.
What is metallic bonding?
The strong electrostatic attraction between positive metal ions and delocalised electrons.
What are delocalised electrons?
Electrons from the outer shell of metal atoms that are free to move.
Why are metals good conductors of electricity?
Because delocalised electrons can move and carry charge.
What does the reactivity series show?
The order of how reactive different metals are.
How do metals form ions?
By losing electrons to form positive ions.
What does a more reactive metal do more easily?
Loses electrons to form positive ions.
How can the reactivity series help you predict reactions?
It shows which metals react more easily with substances like water or acid.
What determines a metal’s reactivity?
How easily it loses electrons.
Name three very reactive metals from the reactivity series.
Potassium, sodium, calcium.
Name two metals that are not very reactive.
Copper and silver.
What happens when metals react with acids?
They form a salt and hydrogen gas.
What does the rate of bubbling (hydrogen) in acid tell you?
How reactive the metal is — faster bubbling = more reactive.
What test confirms hydrogen gas is produced?
The burning splint test — makes a squeaky pop.
What is the word equation for a metal reacting with water?
Metal + Water → Metal Hydroxide + Hydrogen
Which metals react with cold water?
Potassium, sodium, lithium, calcium.
Which metals do not react with water?
Zinc, iron, copper.
What happens when metals react with oxygen?
They form metal oxides.
Do all metals react with oxygen at the same speed?
No — more reactive metals react faster.
What is an ore?
A rock that contains enough metal to make extraction worthwhile.
How can metals be extracted from their ores?
By reduction with carbon, carbon monoxide, or electrolysis.
What does reduction mean in metal extraction?
The removal of oxygen from a metal oxide.
What is the word equation for extracting iron using carbon?
Iron(III) oxide + carbon → iron + carbon dioxide
What metals can be extracted using carbon?
Metals below carbon in the reactivity series (e.g. zinc, iron, lead).
Why can’t metals above carbon be extracted using it?
Carbon is not reactive enough to remove the oxygen.
How are metals above carbon in the reactivity series extracted?
Using electrolysis.
How are unreactive metals like gold found?
As uncombined elements in the Earth’s crust — no extraction needed.
What is oxidation?
Loss of electrons (or gain of oxygen).
What is reduction?
Gain of electrons (or loss of oxygen).
: What is a redox reaction?
A reaction where oxidation and reduction happen at the same time.
What does OIL RIG stand for?
Oxidation Is Loss, Reduction Is Gain (of electrons).
What is an ion-electron equation?
An equation that shows electrons being lost or gained during a reaction.
What is electrolysis?
The splitting up of a compound using electricity.
What is an electrolyte?
A molten or dissolved ionic compound that conducts electricity.
What happens at the positive electrode (anode)?
Negative ions (anions) are oxidised (lose electrons).
What happens at the negative electrode (cathode)?
Positive ions (cations) are reduced (gain electrons).
Why must the electrodes be inert?
So they don’t react with the electrolyte.
Why should you use d.c. in electrolysis?
So the positive and negative terminals stay the same — clear ion movement.
Name two inert electrodes.
Graphite and platinum.
What do you use to connect the electrodes to the power supply?
Crocodile clips and wires.
Why can’t ionic solids be electrolysed?
The ions are fixed in place and can’t move.
Why can molten ionic compounds be electrolysed?
The ions are free to move and carry current.
What happens to positive metal ions during electrolysis?
They go to the negative electrode and are reduced (gain electrons).
What happens to negative non-metal ions during electrolysis?
They go to the positive electrode and are oxidised (lose electrons).
Why is aluminium extracted by electrolysis, not carbon?
It’s too reactive to be reduced by carbon.
What is cryolite used for in aluminium extraction?
It lowers the melting point of aluminium oxide.
What happens at the negative electrode during aluminium extraction?
Al³⁺ ions gain 3 electrons to form aluminium metal.
What happens at the positive electrode during aluminium extraction?
O²⁻ ions lose electrons to form oxygen gas.
What is an electrochemical cell?
A device that creates electricity using a chemical reaction between two different metals in an electrolyte.
What flows in the wires of an electrochemical cell?
Electrons
What flows through the salt bridge?
Ions
What is the function of a salt bridge in an electrochemical cell?
It completes the circuit and balances the charges.
What type of solution is used in the beakers of an electrochemical cell?
An electrolyte — a solution containing ions of each metal.
What should be connected to the electrodes to measure voltage?
A voltmeter.
What are the electrodes usually made of in an electrochemical cell?
The metals being tested.
What equipment connects the power supply in an experiment?
Crocodile clips and wires.
What is the electrochemical series?
A list of metals in order of how easily they form ions.
What is needed to produce a voltage in an electrochemical cell?
: A difference in reactivity between the two metals.
Which metal is oxidised in an electrochemical cell?
The one higher in the electrochemical series.
Which metal is reduced in an electrochemical cell?
The one lower in the electrochemical series.
What makes the voltage in a cell greater?
A greater difference in reactivity between the two metals.
In which direction do electrons flow in an electrochemical cell?
From the metal higher in the series to the one lower in the series.
Why does the more reactive metal lose electrons?
It forms ions more easily — it is oxidised.
What happens in the zinc/copper cell?
A:
Zinc is oxidised: Zn → Zn²⁺ + 2e⁻
Copper is reduced: Cu²⁺ + 2e⁻ → Cu
Overall: Zn + Cu²⁺ → Zn²⁺ + Cu
