Metals Flashcards
Do metals or non-metals generally have low melting and boiling points?
Non-metals generally have low melting and boiling points.
Define the term malleable.
Malleable means the metal can be hammered into different shapes.
Give two properties of metals.
Conduct heat and conduct electricity.
Are malleable and ductile.
Name the products formed when metals with react with acids.
When metals react with acids, a salt and hydrogen are formed.
Name the product formed when copper reacts with oxygen.
copper oxide.
Write the word equation for the general reaction between a metal and water.
metal + water → metal hydroxide + hydrogen
Why can metals conduct electricity?
Metals conduct electricity because they have delocalised electrons which are able to move through the structure.
Which metal is used to make food cans because it is resistant to corrosion?
The metal used to make food cans because it is resistant to corrosion is aluminium.
Why is aluminium a better choice than copper for overhead electrical cables?
Aluminium is a better choice than copper for overhead electrical cables because it has a lower density.
Which metal is used for electrical wiring?
Copper is used for electrical wiring.
Give two properties of copper that make it suitable for electrical wiring.
Copper is suitable for electrical wiring because it has good electrical conductivity and is ductile.
Define the term ductile.
Ductile describes the ability to be drawn into a wire.
What is an alloy?
An alloy is a mixture of metals, where the metals are mixed together physically but are not chemically combined.
State an advantage of using alloys over pure metals.
Advantages of using alloys over pure metals are:
Greater strength
Greater hardness
Describe the structure of an alloy.
Alloys contain atoms of different sizes which distort the regular arrangement of atoms.
Explain why alloys are harder than pure metals.
The increased hardness and strength of an alloy is caused by the different size atoms which distort the regular arrangements of atoms, preventing the layers from sliding over each other easily.
How do properties of alloys differ from pure metals?
Alloys often have greater strength / hardness, or resistance to corrosion / extreme temperatures compared to pure metals.
Give one use of stainless steel.
Cutlery
Name the two main elements in steel alloys.
The two main elements in steel alloys are iron and carbon.
Why is stainless steel used in cutlery?
Stainless steel is used in cutlery because it is hard and resistant to rusting.
What is the general equation for a metal reacting with an acid?
metal + acid → salt + hydrogen
Define the term salt.
A salt is the ionic compound produced when a metal reacts with an acid.
State the meaning of the observation “vigorous” for a metal-acid reaction.
If a metal-acid reaction is described as “vigorous”, it means the reaction is rapid and intense
Give the name of a metal that is above carbon in the reactivity series.
Potassium
Name a metal that is below hydrogen in the reactivity series
Copper
Which metal is more reactive; zinc or iron?
Zinc is more reactive than iron.
Which metal is more reactive; aluminium or zinc?
Aluminium is more reactive than zinc.
What is displacement?
Displacement occurs when a more reactive substance takes the place of a less reactive substance.
What is observed when a more reactive metal displaces a less reactive one from a solution?
When a more reactive metal displaces a less reactive one, the less reactive metal coats the surface or falls out as a solid.
Give two observations made when copper sulfate solution reacts with magnesium.
The blue colour of the solution fades.
Copper forms at the bottom of the beaker.
Why does aluminium not readily react with water and acids?
Aluminium does not readily react with water and acids because it has a protective layer of aluminium oxide.
What is rust?
Rust is the hydrated iron(III) oxide that forms on iron when it corrodes.
Which element does rusting specifically refer to?
Rusting specifically refer to the corrosion of iron.
Write the word equation for the corrosion of iron.
iron + water + oxygen ⟶ hydrated iron(III)oxide
Give two conditions needed for rusting of iron to occur.
Two conditions needed for rusting of iron to occur are water and oxygen.
Give two examples of barrier methods that can prevent rusting.
Painting
Greasing
Why is zinc used to protect iron from corrosion?
Zinc is used to protect iron from corrosion because it is more reactive than iron so will react more readily with oxygen.
How is iron / steel galvanised with zinc?
Electroplating
Define the reactivity series.
The reactivity series orders metals from most reactive to least reactive.
State the method of extraction for metals above carbon in the reactivity series.
Metals above carbon in the reactivity series are extracted by electrolysis.
What determines the extraction method for a metal?
The position of the metal on the reactivity series determines the extraction method.
Which metals must be extracted by electrolysis?
Metals above carbon
What is the extraction method for metals below carbon in the reactivity series?
Metals below carbon in the reactivity series are extracted by heating / reduction with carbon.
Is the extraction of metals by heating with carbon an oxidation or reduction reaction?
The extraction of metals by heating with carbon is a reduction reaction.
Name the raw materials added to a blast furnace for the extraction of iron.
The raw materials added to a blast furnace for the extraction of iron are iron ore, coke and limestone.
Name the main ore of iron.
The main iron ore is haematite.
Why is limestone added to a blast furnace?
Limestone is added to a blast furnace to remove impurities in the ore.
What is molten slag?
Molten slag is calcium silicate formed when calcium oxide reacts with silicon dioxide.
Name the main ore of aluminium.
The main ore of aluminium is bauxite.
Why is aluminium oxide dissolved in molten cryolite during electrolysis?
Aluminium oxide is dissolved in molten cryolite to lower its melting point and reduce the amount of energy required.
What are the electrodes made from in the electrolysis of aluminium oxide
The electrodes are made from graphite / carbon.
Explain why the anode needs to be replaced regularly during the electrolysis of aluminium oxide.
The anode needs to be replaced regularly during the electrolysis of aluminium oxide because the oxygen produced reacts with the carbon electrodes to produce carbon dioxide, causing the anode to wear away.
Why is electrolysis an expensive process?
Electrolysis is expensive as it uses a lot of energy / electricity.
