Page 1 : Question 7: What is soap? How can you make soap in the laboratory?, , ANSWER: The sodium salts of acids are called soaps. A soap is prepared by boiling vegetable oil or fats from, animals along with sodium hydroxide (NaOH)., , We can prepare a soap in the laboratory by following the below mentioned procedure., Required materials:, , 20ml of castor oil (we can also use coconut oil or any other oil), Half teaspoon of sodium hydroxide pellets, , 1 teaspoon of common salt (sodium chloride), and, , Glass rod for stirring, , Procedure :, , © Take the 20ml castor oil in a beaker., , © Mix ¥ teaspoon of sodium hydroxide pellets with about 20m of water to prepare the sodium, hydroxide solution., , © Now, mix the oil with the sodium hydroxide solution., , © Heat the mixture and allow it to boil for about 5 to 10 minutes by constantly stirring it with the glass, rod., , The oil will react with the sodium hydroxide solution to form soap and glycerine., , Oil + Sodium hydroxide + Soap + Glycerine, , «The soap formed can be separated from the mixture by adding a tea spoon of common salt (sodium, chloride) in the beaker., , * After cooling, the solid soap gets separated from the mixture by floating on the top. Thus, a soap is, prepared in the laboratory., , Question 8: How are salts named? Give two examples., , ANSWER: The name of a salt is derived on the basis of the reactants involved in its preparation. The salts are, named after the metal supplied by the base and the radical supplied by the acid., , Example 1: Sodium chloride (common salt) is formed from hydrochloric acid and sodium hydroxide. The, name ‘sodium’ is supplied by the metal of the sodium hydroxide, and the name ‘chloride’ is supplied by the, acid, which is a negative radical., , HCI + NaOH — NaCl + H20, , Example 2: Ammonium sulphate (salt) is formed from sulphuric acid and ammonium hydroxide. The name, ‘ammonium’ is supplied by the ammonium radical of the base, while the name ‘sulphate’ is supplied by the, negative radical of sulphuric acid.