Chemical Changes Flashcards
Oxidation is the… of electrons
Loss
Reduction is the.. of electrons
Gain
How are highly reactive metals extracted
Electrolysis
Why are gold and silver found naturally as elements in the earth’s crust
They are unreactive
What is an ore
A rock containing a metal compound
In terms of oxygen what is oxidation
Oxygen added
In terms of oxygen what is reduction
Loss of oxygen
What type of metals can be extracted through reduction with carbon
Ones less reactive than carbon e.g iron, zinc and lead
(Carbon displaces them from their compound)
What is a spectator ion
Ion that is unchanged in a reaction
What does OIL RIG stand for
Oxidation is loss
Reduction is gain
Both in terms of electrons (it’s the other way round for oxygen)
2 chemical properties of most transition metals
Form ions with different charges
React slowly/ not at all with halogens, oxygen and water
What is electrolysis
Using electricity to extract elements from their compound
What is the electrolyte
The liquid/ solution containing ions and can conduct electricity
In electrolysis what is the electric current passed through
The electrolyte (liquid/ solution containing the ions)
Name for positive electrode
Anode
Name for negative electrode
Cathode
Can solid ionic compounds conduct electricity
No
Ions aren’t free to move and carry charge
Must be molten/ dissolved in water so ions are free to move
Why must the ionic compound in electrolysis be molten/ dissolved in water
Means ions are free to move and can carry charge (conduct electricity) and move to the electrodes
Which electrode do negative ions move to
Positive anode
Which electrode do positive ions move to
Negative cathode
What happens at the cathode for molten compounds
Cathode= negative so attracts positive metal ions
Metals gain electrons to form pure metal
What happens at the anode for molten compound
Anode= positive so attracts negative non-metal ions
Non metal loses electrons and becomes pure non-metal
In electrolysis which out of the metal and non metal forms positive ions, which forms negative
Metal- positive ions
Non-metal- negative ions
If sodium chloride undergoes electrolysis what will be formed at each electrode
Negative Cathode= sodium (metal)
Positive anode= chlorine (non- metal)