Ncert- science – class 7- Chapter 4 – Acids, Bases and Salts 1 Welcome to your Ncert- science - class 7- Chapter 4 – Acids, Bases and Salts 1 1. An example of a solution which is not in equilibrium is: hypotonic solution chemical pH indicator anhydrous solution supersaturated solution None 2. Product of neutralization reactions are always : a salt and a base. a salt and water. an acid and a base an acid and a salt. None 3. A student puts a drop of the reaction mixture of a saponification reaction first on a blue litmus paper and then on a red litmus paper. He may observe that: there is no change in the blue litmus paper and the red litmus paper turns white there is no change in the red litmus paper and the blue litmus paper turns red there is no change in the blue litmus paper and the red litmus paper turns blue no change in colour is observed in both the litmus papers None 4. Turmeric is a natural indicator. On adding its paste to acid and base separately, which colour would be observed ? Pink in acid and yellow in base Yellow in acid and red in base Red in acid and blue in base Yellow in both acid and base None 5. Using toothpaste in daily life is the example of _________. basic reaction none of these neutralization reaction acidic reaction None 6. Which of the following is not a property of acid? Acids change the colour of turmeric Acid turns blue litmus to red. Acids are sour in taste None of these None 7. A solution changes the colour of turmeric paper from yellow to red. The solution is: basic either neutral or acidic acidic neutral None 8. Which of the following acid is present naturally in the spinach? Citrus acid Tartaric acid Oxalic acid Succinic acid None 9. The colour of pH paper strip at the pH valued of 1,7 and 14 will be : Blue, green and red Green, red and blue Red, green and blue Green, blue and red None 10. Which indicator is correctly paired up with its proper color if it were added to a base? i. Litmus - blue ii. Phenolphthalein - pinkiii. Methyl orange - yellow (i) and (iii) only (i) only (iii) only (i), (ii) and (iii) None 11. China rose is which type of indicator? None of the above Olfactory indicator Natural indicator Synthetic indicator None 12. What happens to the colour of litmus paper when you put a drop of acid on it? From blue it turns red It gets destroyed From red it turns blue It is unaffected by acid None 13. When honeybee bites, which chemical enters in to our body? Melittin Magnesium hydroxide Formic acid Calcium formate None 14. From which plant is litmus paper or litmus solution obtained? Hibiscus Lichen Moss Rose None 15. Honey bee stings and ant bites can be _________ using alkaline medicine such as baking powder. None of the above Acidifies Prevented Neutralize None 16. Which one of the following will turn blue-litmus red? Vinegar Lime water Washing soda solution Baking soda solution None 17. Why bee strings are treated by alkaline solutions? Because it is treatable by only alkaline solution. None of these. Because it is acidic in nature. Because it is basic in nature None 18. Which of the following substance enters our body when a red ant bites us? Magnesium hydroxide Melittin Formic acid Calcium Formate None 19. In which of the following, neutralisation reaction takes place? All of the above Treatment of acidity Photosynthesis Breakdown of glucose None 20. What do we observe on pouring acetic acid on red and blue litmus paper? Red litmus turns blue and blue litmus turns red. Red litmus turns blue and blue litmus remains blue. Red litmus remains red and blue litmus turns red. Red litmus becomes colourless and blue litmus remains blue None Time's up Please Share This Share this content Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Leave a Reply Cancel replyCommentEnter your name or username to commentEnter your email address to commentEnter your website URL (optional) Save my name, email, and website in this browser for the next time I comment.
