Question

.
SHORT TYPE QUESTIONS (3 Marks)
Q1. Why does bleaching powder smell strongly of chlorine and does not dissolve completely in water ?
Q2. Hold one moist and one dry strip of blue litmus paper over dry HCI acid gas. Which strip will turn red and why?
Q3. What is Plaster of Paris ? How is it obtained from gypsum ?
Q4. What is the role of toothpastes in preventing cavities?
Q5. Explain why sour substances are effective in cleaning copper vessels ?
Q6. A white powder is added while baking breads and cakes to make them soft and fluffy. What is the name of the powder ? What are its main
ingredients ?
Q7. How washing soda is prepared from baking soda ?
Q8. Though the compounds such as glucose and alcohol have hydrogen atoms in their molecule, yet they are not categorized as acids. Why?
Q9. What is the reaction called when an acid reacts with base to produce salt and water? Give example also.
10. Why pickles and curd are not stored in copper and brass utensils ?
ntor it first turns milky and then​

Answer 1

Answer:

1.Hence, bleaching powder smell strongly of chlorine. ... It contains various other heavy calcium salts in it like calcium chloride, calcium hydroxide and calcium hypochlorite. These salts are insoluble in water. Hence, bleaching powder does not dissolve completely in water.

Answer 2

Answer:

Ans2: Acid can change its colour only in the presence of ions. HCL change its colour only in its aqueous state.So, moist HCL change its colour from blue litmus to red.