Try this as often as you like. You will get a different set of questions each time you attempt this quiz.
Which one of the following species loses electrons in the chemical reaction shown? Mg + Cu2+ → Mg2+ + Cu
Mg
Cu2+
Mg2+
Cu
Oxidation is defined as the loss of electrons. In the following equation, which species is oxidised? 2Na + Cl2 → 2NaCl
Na
Cl2
2NaCl
None of them is oxidised
Which one of the following species loses one or more electrons in the chemical reaction shown? Mg + Cu2+ → Mg2+ + Cu
Mg
Cu2+
Mg2+
Cu
Which of the following statements is correct?
A reducing agent loses electrons in a redox reaction
The oxidising agent is always oxidised in a redox reaction
The oxidising agent always loses electrons
The reducing agent is reduced in a redox reaction
The following reaction takes place when zinc is placed in a copper sulfate solution: Zn + Cu2+ → Zn2+ + Cu Which one of these species is the oxidising agent?
Cu2+
Zn
Zn2+
Cu
Which one of the following substances is a good oxidising agent?
Hydrogen peroxide
Water
Sulfur dioxide
Coke (carbon)
Which one of the following reactions is NOT a redox reaction?
HCl + NaOH → NaCl + H2O
Zn + Cu2+ → Zn2+ + Cu
2Mg + O2 → 2MgO
I2 + 2Fe2+ → 2I− + 2Fe3+
Of the halogens, which one is the most powerful oxidising agent?
Fluorine
Chlorine
Bromine
Iodine
A colourless solution of chlorine is mixed with a colourless solution of potassium bromide (KBr). What colour does the resultant mixture turn?
Red
Yellow
Colourless
Green
A green solution of iron sulfate is placed in a test-tube and chlorine water added. The colour of the expected mixture is most likely to be
brown
green
colourless
red
In the electrochemical series, metals are arranged in order of their tendency to
lose electrons
react with water
become reduced
release halogens from their salts
Of the following metals, which one will lose electrons the easiest?
Potassium
Copper
Magnesium
Zinc
A substance that has the ability to conduct electricity when dissolved in water is known as
an electrolyte
an electrode
a cathode
an anode
What is the name given to the charged species that are attracted to the negative electrode in an electrolyte?
Cations
Cathode
Anions
Anode
What is the oxidising agent in the following reaction? 2Fe2+(aq) + Cl2(g) → 2Fe3+(aq) + 2Cl−(aq)
Cl2(g)
Fe2+(aq)
Fe3+(aq)
Cl−(aq)
Which one of the following shows the correct order for increasing tendency to lose electrons in the electrochemical series?
Copper, lead, zinc and sodium
Silver, tin, potassium and magnesium
Potassium, sodium, lead and gold
Sodium, calcium, tin and silver
When a piece of magnesium ribbon is placed in a beaker of copper sulfate solution, which one of the following is most likely to happen?
The blue colour of the copper sulfate solution gets lighter.
The blue colour of the copper sulfate solution gets darker.
A vigorous reaction immediately takes place, with the release of a lot of heat.
The magnesium catches fire.
In which one of the following reactions is chlorine oxidised?
F2 + 2Cl−(aq) → Cl2(aq) + 2F−(aq)
2ClO3− + 12H+ + 10e− → Cl2 + 6H2O
2Na(s) + Cl2(g) → 2NaCl(s)
Cl2 + 2e− → 2Cl−
What is the oxidation number of vanadium in the compound NaVO3?
+5
+2
0
-1
What happens to Fe2+ in the following reaction? Sn4+ + Fe2+ → Sn3+ + Fe3+
It undergoes oxidation and loses electrons.
It undergoes oxidation and gains electrons.
It undergoes reduction and gains electrons.
It undergoes reduction and loses electrons.
What happens to vanadium during the reaction VO2+ (aq) → VO3−(aq)?
It undergoes oxidation and its oxidation number changes from +4 to +5.
It undergoes oxidation and its oxidation number changes from +2 to +4.
It undergoes reduction and its oxidation number changes from +2 to –1.
It undergoes reduction and its oxidation number changes from +4 to +2.
Which statement is a correct description of electron loss in the following reaction? 2Al + 3S → Al2S3
Each aluminium atom loses three electrons.
Each aluminium atom loses two electrons.
Each sulfur atom loses two electrons.
Each sulfur atom loses three electrons.
What happens to the Cr3+(aq) ion when it is converted to CrO42−(aq) ion?
Its oxidation number decreases and it undergoes reduction.
Its oxidation number decreases and it undergoes reduction.
Its oxidation number decreases and it undergoes oxidation.
Its oxidation number increases and it undergoes reduction.
Consider the following reaction: H2SO3 + Sn4+ + H2O → Sn2+ + HSO4− + 3H+ Which statement is correct?
H2SO3 is the reducing agent because it undergoes oxidation.
H2SO3 is the reducing agent because it undergoes reduction.
Sn4+ is the oxidizing agent because it undergoes oxidation.
Sn4+ is the reducing agent because it undergoes oxidation.
In which of the following conversions does the oxidation number of an element decrease by 3?
Potassium
Copper
Magnesium
Zinc