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. Using toothpaste in daily life is the example of _________. neutralization reaction acidic reaction none of these basic reaction None 2. From which plant is litmus paper or litmus solution obtained? Moss Hibiscus Rose Lichen None 3. An example of a solution which is not in equilibrium is: anhydrous solution supersaturated solution chemical pH indicator hypotonic solution None 4. Why bee strings are treated by alkaline solutions? Because it is acidic in nature. None of these. Because it is basic in nature Because it is treatable by only alkaline solution. None 5. 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 becomes colourless and blue litmus remains blue Red litmus remains red and blue litmus turns red. Red litmus turns blue and blue litmus remains blue. None 6. Honey bee stings and ant bites can be _________ using alkaline medicine such as baking powder. None of the above Prevented Neutralize Acidifies None 7. Turmeric is a natural indicator. On adding its paste to acid and base separately, which colour would be observed ? Yellow in acid and red in base Red in acid and blue in base Yellow in both acid and base Pink in acid and yellow in base None 8. When honeybee bites, which chemical enters in to our body? Formic acid Melittin Magnesium hydroxide Calcium formate None 9. China rose is which type of indicator? Synthetic indicator None of the above Olfactory indicator Natural indicator None 10. 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 red litmus paper and the blue litmus paper turns red no change in colour is observed in both the litmus papers there is no change in the blue litmus paper and the red litmus paper turns white there is no change in the blue litmus paper and the red litmus paper turns blue None 11. Which of the following substance enters our body when a red ant bites us? Calcium Formate Magnesium hydroxide Melittin Formic acid None 12. Which of the following acid is present naturally in the spinach? Citrus acid Succinic acid Tartaric acid Oxalic acid None 13. What happens to the colour of litmus paper when you put a drop of acid on it? It gets destroyed From red it turns blue From blue it turns red It is unaffected by acid None 14. A solution changes the colour of turmeric paper from yellow to red. The solution is: acidic basic either neutral or acidic neutral None 15. Which one of the following will turn blue-litmus red? Washing soda solution Vinegar Lime water Baking soda solution None 16. 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 (iii) only (i), (ii) and (iii) (i) only None 17. Which of the following is not a property of acid? None of these Acid turns blue litmus to red. Acids are sour in taste Acids change the colour of turmeric None 18. Product of neutralization reactions are always : an acid and a base an acid and a salt. a salt and water. a salt and a base. None 19. In which of the following, neutralisation reaction takes place? All of the above Photosynthesis Treatment of acidity Breakdown of glucose None 20. The colour of pH paper strip at the pH valued of 1,7 and 14 will be : Green, blue and red Green, red and blue Blue, green and red Red, green and 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.
