In this exercise you should click the SHOW ALL QUESTIONS button.
Type the formula for the compounds or species indicated. Don't worry about superscripts and subscripts: if you type SO42- the program will interpret it as SO42-. Do pay attention to capital and lower case letters though. After you have typed each formula, click on CHECK to mark it. Clicking on HINT will reveal the next letter of the answer -- but you will lose marks by doing so.
Reaction one
Potassium permanganate solution is decolourised by acidified iron(II) sulfate.
A product of this reaction turns potassium thiocyanate solution blood-red.
Type the formula for the oxidising agent.
Type the formula for the reducing agent.
Type the formula for the product of the oxidation reaction.
Type the product of the reduction reaction.
What is the blood-red species?
Reaction two
Potassium dichromate solution is acidified with acetic acid.
When sodium sulfite solution is added the orange solution turns green.
One of the products of this reaction forms a white precipitate with barium chloride.
Type the formula for the species being oxidised in this reaction.
Type the formula of the species being reduced in this reaction.
What is the product of the oxidation reaction?
What is the formula for the white precipitate?
What is the product of the reduction reaction?
Reaction three
Yellow-green chlorine gas is bubbled through colourless sodium bromide solution, turning it orange.
What is the oxidising agent in this reaction?
What is reduced during this reaction?
What is the reducing agent?
What is the product of the oxidation reaction?
Reaction four
A strip of zinc metal left overnight in lead nitrate solution is covered in shiny crystals.
What is the reductant in this reaction?
What is the product of the reduction reaction?
What is oxidised in this reaction?
What is the oxidant?
What is the product of the oxidation reaction?
Reaction five
A small piece of brown copper metal is placed in a beaker with colourless concentrated nitric acid. A brown gas is produced and the liquid turns blue/green.
Identify the brown gas.
What species reacted to form this gas?
Identify the blue/green species.
What is the oxidising agent?
What species is reduced?
What species is oxidised?
What is the reductant?
Reaction six
A piece of magnesium ribbon burns brightly when held in a Bunsen flame.
Write the formula for the product of this reaction.
What is the oxidant?
Write the formula for the species formed in the oxidation reaction.
Write the species formed in the reduction reaction.
What is the reducing agent in this reaction?
Reaction seven
A strip of copper after being left overnight in silver nitrate solution.
What colour would the original silver nitrate solution have been?
What species is responsible for the faint blue colour of the solution shown in the photograph?
Identify the white substance which has formed on the copper strip.
What is the oxidising agent in this reaction?
What is the reductant?
Reaction eight
This is an old-fashioned breathalyser, used to detect excess alcohol in the breath of motorists.
As the subject blows into the tube from the left, orange crystals turn green.
What anion is likely to be in the crystals?
What is the green species?
What ion must also be present for this colour change to occur?
