Patterns Of Reactivity- Topic 3 Flashcards
what is the General equation for reacting metals with oxygen?
Metal+oxygen—>metal oxide
Describe coppers flame, equation and the colour of oxide at end.
Copper+oxygen—>copper oxide
No flame (may see blue), glowing
Oxide= Black on surface
Describe iron’s flame, equation and the colour of oxide at end.
Iron+oxygen—>iron oxide
Bright yellow sparks
Dark grey
Describe magnesium’s flame, equation and the colour of oxide at end.
Magnesium+oxygen—>magnesium oxide
Bright white light
White powder,ash
Give the General equation for metals reacting with water
Metal+water—>metal hydroxide+hydrogen
How are the metal and water reactions similar?
All react vigorously
Give off gas & heat
Move across surface
How are the metal and water reactions different?
Some react quicker than others
Some produce flames and some don’t
Potassium catches fire + burns with a lilac flame
List 3 safety precautions taken when using these metals with water.
Wear safety goggles
Use tongs
Stand back during reaction
If close to others use a screen
Metals are stored under oil
List the hazard symbols on each metal jar.
Corrosive
Flammable
Why are lithium, sodium + potassium all stored under oil in their jars?
To stop them from reacting with air
What observation is taken from calcium when reacted with water?
Produces bubbles + heat. Alkaline.
What observation is taken from magnesium when reacted with water?
Reacts slowly, pops.
What observation is taken from copper when reacted with water?
Does not react
What observation is taken when any metal reacts with water?
All produce hydrogen gas
What is produced when metals react with water?
Metal hydroxide + hydrogen
Give the word equations for calcium reacting with water.
Calcium+ water—>calcium hydroxide + hydrogen
Give the word equations for magnesium reacting with water.
Magnesium+water—>magnesium hydroxide+hydrogen
Give the word equations for copper reacting with water.
Copper+water—>no reaction
What is the General equation for metals reacted with acid.
Metal+acid—>salt+hydrogen
What is usually produced when a metal reacts with an acid?
Hydrogen gas + salt
Which metals would you not try putting into acid?
Potassium/sodium/lithium- explosive
What happens when aluminium reacts with acid (unusual case)
High up in reactivity series but takes a while to react with acid
With dilute acid (water+acid), it should react fast. A gas will be given off.
Why does aluminium take a while to react with acid?
Aluminium oxide layer takes long to dissolve. This protects + stops it from reacting.
Why does aluminium resist corrosion?
Forms a layer of aluminium oxide, (protects aluminium + stops it from reacting)
Name the reactivity series from most reactive to least reactive.
Potassium
Sodium
Lithium
Calcium
Magnesium
Aluminium
Zinc
Iron
Copper
Silver
Gold
Name a mnemonic for the reactivity series.
Please
Send
Little
Charlie’s
Monkeys
And
Zebras
In
Cages
Securely
Guarded
Name two things about lead.
Very unreactive in cold water
Surface of metallic lead is protected by layer of lead oxide.
What is the word equations for magnesium and sulfuric acid.
Magnesium+sulfuric acid —>magnesium sulfate + hydrogen
What is a displacement reaction?
Eg calcium + zinc sulfate—>calcium sulfate + zinc
Gold+iron sulfate—>no reaction
A more reactive metal will displace a less reactive metal from its compound. This reaction is observed by colour changes or fizzing or heat being evolved. We call this a displacement reaction
Name something silver was used for in the past and why is was considered a good idea.
Used to make coins, unreactive, desirable and malleable metal.
What is copper used for and why?
Used to make electrical cables+ wires as it conducts electricity and is cheap to produce.
Why do we know so little about the Iron Age?
Iron had corroded/rusted
What happens when magnesium mixes with copper sulfate solution. Give the word equation as well.
Copper solid forms and blue solution fades
Magnesium+copper sulfate—>magnesium sulfate + copper
What happens with an iron nail in water + air?
Rust
What happens with an iron nail in dry air?
No rust
What happens with an iron nail in water?
A little rust/no rust
What happens with an iron nail in water an air+zn wrap
No rust
What happens with an iron nail in salty water + air?
Lots of rust
What do we need for rust?
Iron, oxygen and water for iron to rust.
What is the word equation for rust?
Iron+ oxygen+ water—> hydrated iron oxide (rust)
What is another name for rust?
Hydrated iron oxide
What do we need for rusting to take place?
Oxygen and water
What can we do to prevent iron from rusting!
Paint/oil
Plastic coating
Galvanising
Sacrificial protection
Give examples of metals that will rust iron
Copper, silver
Give examples of metals that will not rust iron
Zinc, magnesium
What is plastic coating?
Prevents air+ moisture from reaching iron
What is galvanising?
When iron object is coated in more reactive metal.
What can be used to galvanise iron?
Zinc, chromium
What is painting/oiling?
Cheapest method of preventing rust
What is sacrificial protection?
Used to attach zinc blocks to ships. Zn acts in preference to iron. The water will react with zinc before it reacts with iron as it is more reactive. prevents iron from rusting.
Give the best way to prevent a gate from rusting?
Paint it
Give the best way to prevent the hull of a ship from rusting?
Sacrificial protection
Give the best way to prevent machinery from rusting?
Oil
Give the best way to prevent an iron nail from rusting?
Galvanise it
