Acid base and salt part 3

Acid base and salt part 3

1. Write the chemical formulae of washing soda and baking soda. Which one of these two is an ingredient of antacids? How does it provide relief in stomach ache?                                                        
2. (a) Give Arrhenius definition of an acid and a base. (b) Choose strong acid and strong base from the following; CH₃COOH, NH₄OH, KOH, HCL
3. A metal compound A, react with dilute hydrochloric acid to produce effervescence. The gas evolved extinguishes a burning candle. Write a balanced chemical equation for the reaction if one of the compounds formed is calcium chloride.
4. Why does distilled water not conduct electricity whereas rainwater does?
5. A milkman adds a very small amount of baking soda to fresh milk. (a) Why does he shift the pH of the fresh milk from 6 to slightly alkaline? (b) What do you expect to observe when the milk comes to a boil? (c) Why does this milk take a long time to set as curd?
6. Baking soda is used in small amount in making bread and cake. It helps to make these soft and spongy. An aqueous solution of baking soda turns red litmus blue. It is also used in soda acid fire extinguisher. Use this information to answer the following questions; (i) How does Baking soda help to make cakes and bread soft and spongy?  (ii) How does it help in extinguishing fire? (iii) Is the pH value of baking soda solution lower than or higher than?                                                            
7. A student dropped few pieces of marble in dilute Hydrochloric acid contained in a test tube. The evolved gas was passed through lime water. What change would be observed in lime water? Write balanced chemical equations for the reaction when (a) gas was evolved (b) gas was passed through lime water.                                     
8. Answer the following; (a) Why is formula of plaster of Paris written as CaSO4. ½ H2O? How is it possible to have half a water molecule attached to CaSO4?  (b) Why is Sodium Hydrogen Carbonate an essential ingredient in most antacids? (c) When electricity is passed through an aqueous solution of sodium chloride, three products are obtained. Why the process is called chlor-alkali process?        
9. Name the products formed in each case when (a) hydrochloric acid react with caustic soda. (b) Granulated zinc reacts with caustic soda. (c) Carbon dioxide is passed into lime water.