Electrolysis
Oxidation takes place at the ......................
(cathode / anode)
Anode
in a voltaic/galvanic cell, the more reactive metal is placed at the ...................... (anode/ cathode).
Anode
Magnesium sulfate, carbon dioxide, water
Chlorine gas is liberated at the anode in the electrolysis of:
(a) molten sodium chloride
(b) dilute sodium chloride solution
(c) concentrated sodium chloride solution
(a) and (c)
In an electric cell, the cathode is also known as the .................... (positive / negative) electrode.
This is where .......................... (oxidation / reduction) takes place.
positive,
reduction
Bonus (100 points): Name this type of reaction.
Calcium nitrate, lead
Displacement reaction
In the electrolysis of dilute silver nitrate solution, name the products formed at the:
(a) positive electrode
(b) negative electrode
(a) silver
(b) water and oxygen
What is the difference between an electrolysis cell and an electric (or voltaic or galvanic) cell?
An electrolytic cell uses electrical energy to drive a non-spontaneous chemical reaction.
An electric cell used a spontaneous redox reactions to produce electrical energy.
What will observed when aqueous ammonia is added to a solution of copper (II) sulfate until in excess.
The ppt dissolves in excess aqueous ammonia forming a dark blue solution.
What would be the effect on the colour of the electrolyte during the electrolysis of dilute copper (II) sulfate solution with copper electrodes?
(a) It would fade
(b) It would grow darker
(c) It would not change
(c) It would not change
Electric cell A consists of a copper electrode and a magnesium electrode placed in a solution of dilute sodium chloride.
What will be observed at the copper electrode?
(a) Hydrogen gas will be formed.
(b) The electrode will lose mass over time.
(c) The electrode will gain mass over time.
(a) Hydrogen gas will be formed
Name the four possible indicators that show if a reaction is a redox reaction or not.
1. Gain/loss of oxygen
2. Gain/loss of hydrogen
3. Gain/loss of electrons
4. Increase/decrease in oxidation state
(a) anode?
(b) cathode?
(a) piece of copper metal
(b) the metal spoon
An electric cell consists of a copper electrode and a magnesium electrode placed in a solution of dilute copper (II) sulfate.
What will be observed at the magnesium electrode?
(a) Oxygen gas will be formed.
(b) The electrode will lose mass over time.
(c) The electrode will gain mass over time.
(b) The electrode will lose mass over time.
Name and give the chemical formulae of the products of the reaction between aqueous ammonium nitrate and aqueous sodium hydroxide over gentle heat.
Ammonia, NH3
Sodium nitrate, NaNO3
Water, H2O