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. Milk of magnesia Mg(OH) 2 is a/an: alkali antacid rock salt acid None 2. Which pair of indicators shows no colour change when used with acidic solutions? Litmus and China rose China rose and phenolphthalein Turmeric and China rose Turmeric and phenolphthalein None 3. Which of the following set of substances contain acids only? Grapes, lime water Curd, vinegar Curd, milk of magnesia Vinegar, soap None 4. Which base is employed as the electrolyte in alkaline batteries? KOH Al(OH)3 NaOH FeOH None 5. One of the following that does not inject an acidic liquid into the skin through its sting. This is Wasp Ant Honey bee Nettle leaf hair None 6. Which substance when dissolved in water changes red litmus paper to blue. All of the above Shower cream Milk of magnesia Tooth paste None 7. Which of the following is a use of Al(OH)3 It is used as an antacid It is used in fire extinguisher as a foaming agent It is used in the preparation of fertilizers It is used in removing stains of grease from cloths None 8. To protect tooth decay we are advised to brush our teeth regularly. The nature of the toothpaste commonly used is: Acidic Basic Neutral Corrosive None 9. 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 A and C C and B B and D None 10. Which of the following acid is present in the sting of an ant? Oxalic acid Tartaric acid Formic acid Succinic acid None 11. 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? Slaked lime Hydrochloric acid Salt Water None 12. Phenolphthalein is a synthetic indicator and its color in acidic and basic solutions, respectively are: blue and red pink and colorless colorless and pink red and blue None 13. 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. II IV III I None 14. The acid used in the making of vinegar is: acetic acid sulphuric acid formic acid nitric acid None 15. An aqueous solution turns red litmus blue. Excess addition of which of the following solutions would reverse the change? Water Hydrochloric acid Ammonium hydroxide solution None of these None 16. Which of the following is a use of sodium hydroxide? It is an important constituent of drain cleaners. It is used in the manufacture of soaps and paper. It is used in the manufacture of synthetic fibers like rayon. All of the above. None 17. Which of the following set of substances contain acids only? Vinegar, soap Grapes, lime water Curd, milk of magnesia Curd, vinegar None 18. In which of the following chemical processes does the reaction mixture become hot? Mixing two samples of an acid Evaporating liquid water Mixing two samples of a base Neutralisation of an acid with a base None 19. 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 Ethanoic acid Hydrochloric acid None 20. Which one of the following types of medicines is for treating indigestion ? Analgesic Antiseptic Antacid Antibiotic 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.