Advertisements
Advertisements
Question
State the observation at the anode and at the cathode during the electrolysis of :
Fused lead bromide using graphite electrodes
Solution
Observations:
Anode: Dark reddish brown fumes of bromine evolve at the anode.
Cathode: Greyish white metal lead is formed on the cathode.
APPEARS IN
RELATED QUESTIONS
Molten lead bromide conducts electricity. It is called an ______. It is composed of lead ______ and bromide ______. The lead ions are ______ charged and are called ______. The bromide ______ are ______ charged and are called ______.
State your observation for the following electrolytic reaction
Aqueous copper sulphate is electrolysed between copper electrodes.
Explain the term : Electro metallurgy
How is the passage of electricity through an electrolyte different from the passage of electricity through a copper wire?
Choose the correct words to fill in the blanks.
Cations are formed by _______ (loss/ gain) of electrons and anions are formed by ________( loss/gain) of electrons.
Explain how electrolysis is an example of Redox reaction.
The following is an extract from metals in the service of man, Alexander and street /Pelican 1976': Alumina (aluminium oxide) has a very high melting point over 2000oC, so that I cannot readily be liquefied. However, conversion of alumina to aluminium and oxygen, by electrolysis, an occur when it is dissolved in some other substance.
(a) Which solution is used to react with bauxite as first step in obtaining pure aluminium oxide?
(b) The aluminium oxide for the electrolytic extraction of aluminium is obtained by heating aluminium hydroxide. Write the equation for this reaction.
(c) Name the element which serves both as the anode and the cathode in the extraction of aluminium.
(d) Write the equation for the reaction that occurs at the cathode during the extraction of aluminium.
(e) Write the equation for the reaction that occurs at the cathode during extraction of aluminium by electrolysis.
(f) Give the equation for the reaction that occurs at the anode when aluminium is purified by electrolysis.
During the electrolysis of copper (II) sulphate solution using platinum as cathode and carbon as anode:
- What do you observe at the cathode and at the anode?
- What change is noticed in the electrolyte?
- Write the reactions at the cathode and at the anode.
When fused lead bromide is electrolyzed we observe
M is a metal above hydrogen in the activity series and its oxide has the formula M2O. The oxide when dissolved in water forms the corresponding hydroxide which is a good conductor of electricity. In the above context answer the following:
- What kind of combination exists between M and O?
- How many electrons are there in the outermost shell of M?
- Name the group to which M belongs.
- State the reaction taking place at the cathode.
- Name the product at the anode.
