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