41.

Write the equation for the following reaction:

Dilute nitric acid and copper:

What property of hydrogen chloride is demonstrated when it is collected by downward delivery(upward displacement)?

Why is hydrogen chloride not collected over water?

Dilute hydrochloric acid and sodium thiosulphate

Write the equation for the following reaction:
Dilute hydrochloric acid and lead nitrate solution.

Here is an electrode reaction

Cu---> Cu²⁺ +2e^-

At which electrode (anode or cathode) would such a reaction take place? Is this an example of oxidation or reduction ?

 A solution contains magnesium ions (Mg²⁺) iron (II) ions (Fe²⁺) and copper ions (Cu²⁺). On passing an electric current through this solution which ions will be the first to be discharged at the cathode? Write the equation for the cathode reaction.

The following is a sketch of an electrolytic cell used in the extraction of aluminium:

(i)  What is the substance of which the electrodes A and B made? 

(ii)  At which electrode (A and B) is the aluminium formed? 

(iii)  What are the two aluminium compounds in the electrolyte C? 

(iv) Why is it necessary for electrode B to be continuously replaced?

From the equation:

C+2H₂SO₄ ----> CO­₂ +2H₂O +2SO₂­

Calculate :

i)  The mass of carbon oxidised by 49 g of sulphuric acid (C=12; relative molecular mass of sulphuric acid =98)

ii)The volume of sulphur dioxide measured at STP, liberated at the same time (volume occupied by 1 mole of a gas at STP is 22.4 dm³

Why is carbon tetrachloride, which is a liquid, non -electrolyte?