Explain the term racidity. Write any two methods to prevent ( or retard) the development of rancidity in fat and oil containing foods. Name another damaging effect caused by the same natural process which produces rancidity.

Which term is used to indicate the development of unpleasant smell and taste in fat and oil containing foods due to aerial oxidation (when they are kept exposed for a considerable time) ?

What is the general name of the chemicals which are added to fat and oil containing foods to prevent the development of rancidity?

Name two anti-oxidants which are usually added to fat and oil containing foods to prevent rancidity.

(a) Explain the term "rancidity". What damage is caused by rancidity ? (b) What type of chemical reaction is responsible for causing rancidity ? (c ) State and explain the various methods for preventing or retarding rancidity of food.

Which of the following cannot be used to prevent food containing fats and oils from becoming rancid?

(a) Name the reaction which is usually sued in the conversion of vegetable oils to fats. Explain the reaction involved in detail .Write a chemical equation to illustrate your answer (b) What is saponification? Write the chemical equation of the reaction involved in this process. Name all the substances which take part in this process and also those which are formed. (c ) Why does micelle formation take place when soap is added to water ? will a micelle be formed in other solvents like ethanol also?

(a) Name the metal which is extracted from the ore called 'rock salt' (b) name two ores of zinc. Write the names of the chemical compounds present in them and give their chemical formulae. (c) Explain how, mercury is extracted from its sulphide ore (cinnabar). give equations of the reactions involved. (d) In the electrolytic refining of a metal M, what would you take as anode, cathode and electrolyte? (e). Name any five metals which are purified by electrolytic refining method.