Science
Acids, Bases, and Salts
अम्ल, क्षारक और लवण
In Class 10 Science, under the chapter Chemical Substances – Nature and Behaviour, students study acids, bases, and salts through their properties, reactions, and everyday examples. The topic explains how these substances behave with indicators and with one another, including neutralisation, and introduces the formation and practical importance of common salts.
Practice questions
Baking powder produces carbon dioxide in moist dough but generally does not react strongly in a dry container. What is the best reason?Why can excessive heating of gypsum reduce the quality of plaster of Paris?Phenolphthalein is pink and methyl orange is yellow in a solution. What is the nature of the solution?If equal volumes of acid and base are mixed but the solution remains acidic, which reason may be correct?Turmeric turns reddish-brown and red litmus turns blue in a solution. Which ion is likely to be in excess?How can sodium hydroxide form sodium carbonate when kept in open air?A solution has pH 13. After adding water, its pH becomes 11. What is the correct conclusion?On strong heating of baking soda, the gas evolved turns lime water milky. What is the name of the remaining solid?The pH of a lake decreases due to acid rain. Adding lime raises the pH. What type of process is this?Why does pH increase when hydroxide ions are added to an acidic solution?Why can the bleaching property of bleaching powder decrease when it is kept in a moist open place?If a gas turns moist red litmus blue but has no effect on dry red litmus, what is the conclusion about the gas?A solution has pH 7 and conducts electricity. Which solution could it be?Why does acid rain slowly corrode a marble statue?A small amount of base is added to an acidic solution and pH changes from 3 to 5. How much did the acidity change approximately?How does basic toothpaste help prevent tooth decay?Magnesium gives a gas in an acidic solution, but calcium carbonate gives a different gas in the same solution. Which pair is correct?A substance forms salt and water with an acid but does not dissolve in water. What is it?Methyl orange is red in a solution. On adding base, its colour becomes yellow. What is the conclusion?Sodium chloride solution has pH near 7. Still it conducts electricity. What does this prove?