The metals high up in the reactivity series are very reactive. They cannot be obtained from their compounds by heating with carbon. For example, carbon cannot reduce the oxides of sodium, magnesium, calcium, aluminium, etc., to the respective metals. This is because these metals have more affinity for oxygen than carbon. These metals are obtained by electrolytic reduction. For example, sodium, magnesium and calcium are obtained by the electrolysis of their molten chlorides. The metals are deposited at the cathode (the negatively charged electrode), whereas, chlorine is liberated at the anode (the positively charged electrode).
1. Cathode electrodes are _________ charged.
a. Positively
b. Negatively
2. Can Calcium oxides be reduced by carbon?
a. YES
b. NO
3. Anode electrodes are _____charged.
a. Positively
b. Negatively
4. Metals which have more affinity for oxygen than carbon.
a. Magnesium
b. Sodium
c. Calcium
d. All of the above
5. _____ are obtained by molten chlorides.
a. Magnesium
b. Sodium
c. Calcium
d. All of the above
