Ncert- science – class 7- Chapter 4 – Acids, Bases and Salts 2 Welcome to your Ncert- science - class 7- Chapter 4 – Acids, Bases and Salts 2 1. Which of the following acid is present in the sting of an ant? Tartaric acid Oxalic acid Succinic acid Formic acid None 2. Which base is employed as the electrolyte in alkaline batteries? NaOH Al(OH)3 KOH FeOH None 3. Which substance when dissolved in water changes red litmus paper to blue. All of the above Shower cream Tooth paste Milk of magnesia None 4. One of the following that does not inject an acidic liquid into the skin through its sting. This is Nettle leaf hair Honey bee Wasp Ant None 5. On washing with soap, a turmeric stain on the cloth turns to red becauseA. soap solution is alkaline.B. soap solution is acidic.C. turmeric contains a natural indicator.D. turmeric contain litmus.Select the correct alternative. A and D C and B A and C B and D None 6. Phenolphthalein is a synthetic indicator and its color in acidic and basic solutions, respectively are: pink and colorless blue and red red and blue colorless and pink None 7. Which of the following set of substances contain acids only? Grapes, lime water Vinegar, soap Curd, milk of magnesia Curd, vinegar None 8. The acid used in the making of vinegar is: acetic acid formic acid sulphuric acid nitric acid None 9. Milk of magnesia Mg(OH) 2 is a/an: antacid acid rock salt alkali None 10. In which of the following chemical processes does the reaction mixture become hot? Neutralisation of an acid with a base Mixing two samples of an acid Mixing two samples of a base Evaporating liquid water None 11. An aqueous solution turns red litmus blue. Excess addition of which of the following solutions would reverse the change? Water Ammonium hydroxide solution Hydrochloric acid None of these None 12. Which pair of indicators shows no colour change when used with acidic solutions? Turmeric and phenolphthalein Turmeric and China rose Litmus and China rose China rose and phenolphthalein None 13. Which of the following set of substances contain acids only? Grapes, lime water Curd, vinegar Curd, milk of magnesia Vinegar, soap None 14. Which of the following is a use of Al(OH)3 It is used in fire extinguisher as a foaming agent It is used as an antacid It is used in the preparation of fertilizers It is used in removing stains of grease from cloths None 15. A drop of a liquid sample was put on the pH paper. The color of the pH paper turned blue. The liquid sample could be that of: Sodium bicarbonate solution Lemon juice Hydrochloric acid Ethanoic acid None 16. To protect tooth decay we are advised to brush our teeth regularly. The nature of the toothpaste commonly used is: Corrosive Acidic Neutral Basic None 17. Which of the following is a use of sodium hydroxide? All of the above. It is an important constituent of drain cleaners. It is used in the manufacture of synthetic fibers like rayon. It is used in the manufacture of soaps and paper. None 18. Manisha took a little bit of soil from her garden and mixed it with water. When she dipped a blue litmus in it, the litmus turned red. By adding which of the following to her garden will she get better plant growth? Water Hydrochloric acid Slaked lime Salt None 19. In an experiment to test the pH of a given sample using pH paper, four students recorded the following observations :SamplepH Paper ColorWaterBlueDilute HClRedDilute NaOHBlueDilute Ethanoic AcidOrange Which one of the above observations is incorrect. I II IV III None 20. Which one of the following types of medicines is for treating indigestion ? Antibiotic Analgesic Antacid Antiseptic 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.
