This quiz works best with JavaScript enabled. Home > Class 7 > Class 7 Science Chapter 4 Bases – Quiz 23 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 7 Science Chapter 4 Bases Quiz 23 (25 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. If the H$^{+}$ of a solution is 9.1 x 10$^{-3}$, what is the pH? A) 2.0. B) 3.0. C) 11. D) 12. Show Answer Correct Answer: A) 2.0. 2. What ions are there more of in basic solutions? A) H+ (H3O+). B) OH-. C) All the above. D) None of the above. Show Answer Correct Answer: B) OH-. 3. Which of the following is an example of a base? A) Sodium hydroxide (NaOH). B) Calcium carbonate (CaCO3). C) Ammonia (NH3). D) All of the above. Show Answer Correct Answer: D) All of the above. 4. Select the formula for the following base:chromium (III) hydroxide A) Cr(OH)$_{3}$. B) Cr$_{3}$OH. C) All the above. D) None of the above. Show Answer Correct Answer: A) Cr(OH)$_{3}$. 5. Which substance has a pH less than 7? A) Acids. B) Bases. C) All the above. D) None of the above. Show Answer Correct Answer: A) Acids. 6. What is the first step of DNA Replication? A) Helicase unwinds the DNA strands. B) DNA polymerase adds nucleotides. C) RNA polymerase adds nucleotides. D) Helicase zips up the DNA. Show Answer Correct Answer: A) Helicase unwinds the DNA strands. 7. A solution with a pH of 10 is mixed with a solution with a pH of 4. What would the pH of the mixture most likely be? A) 10. B) 4. C) 40. D) 7. Show Answer Correct Answer: D) 7. 8. In a titration experiment, what is the purpose of using an indicator? A) To measure the temperature change. B) To determine the endpoint of the reaction. C) To increase the reaction rate. D) To neutralize the acid. Show Answer Correct Answer: B) To determine the endpoint of the reaction. 9. Who was given credit for determining the shape of DNA? A) Avery. B) Watson and Darwin. C) Watson and Crick. D) Franklin and Crick. Show Answer Correct Answer: C) Watson and Crick. 10. A pH of 8-14 is a(n) ..... ? A) Base. B) Acid. C) Neutral. D) Phenolphthalein. Show Answer Correct Answer: A) Base. 11. Which of the following latin roots means to say? A) Dict. B) With. C) Spec. D) Vis. Show Answer Correct Answer: A) Dict. 12. What PH number would be an example of a mild base? A) 14. B) 9. C) 5. D) 1. Show Answer Correct Answer: B) 9. 13. What is the name of Mg(OH)$_{2}$ A) Magnesium hydroxide acid. B) Hydromagnesium acid. C) Magnesium oxygen hydride. D) Magnesium hydroxide. Show Answer Correct Answer: D) Magnesium hydroxide. 14. Acid:substance that in solution releases the hydrogen ions (H $^{+1} $) that it possesses. A) Arrhenius Theory. B) Theoria de bronsted. C) REACCIONES DE ACIDO. D) N.A. Show Answer Correct Answer: A) Arrhenius Theory. 15. Nucleotides contain each of the following except: A) Phosphate. B) Nitrogen base. C) Glycerol. D) Pentose sugar. Show Answer Correct Answer: C) Glycerol. 16. Does not react with blue litmus paper leaving it blue A) Acid. B) Base. C) Neutral. D) None of the above. Show Answer Correct Answer: B) Base. 17. CO$_{3}$$^{2-}$(aq)+H$_{2}$O(l) $\rightarrow$ HCO$_{3}$$^{-}$(aq)+OH$^{-}$(aq)Using the above reaction, which compound is the conjugate base? A) CO$_{3}$$^{2-}$. B) H$_{2}$O. C) HCO$_{3}$$^{-}$. D) OH$^{-}$. Show Answer Correct Answer: D) OH$^{-}$. 18. Which of these formulas represents a base A) HBr. B) HF. C) HNO$_{3}$. D) Any otheruce. Show Answer Correct Answer: D) Any otheruce. 19. State all digits that used in base 4. A) 0, 1, 2. B) 0, 1, 2, 3. C) 0, 1, 2, 3, 4. D) 1, 2, 3. Show Answer Correct Answer: B) 0, 1, 2, 3. 20. Select the formula for the following acid:hydroiodic acid A) HI. B) This $ _ {4} $. C) This $ _ {3} $. D) H$_{2}$I. Show Answer Correct Answer: A) HI. 21. Solve 3$^{26}$ = 3$^{4x + 2}$ A) X = 6. B) X = 5. C) X = 3. D) X =-4. Show Answer Correct Answer: A) X = 6. 22. Solutions that have more H+ ions than OH-ions are A) Acids. B) Bases. C) Enzymes. D) Neutral. Show Answer Correct Answer: A) Acids. 23. Which of the following bases is commonly used in soap making? A) Sodium hydroxide. B) Calcium hydroxide. C) Ammonium hydroxide. D) Barium hydroxide. Show Answer Correct Answer: A) Sodium hydroxide. 24. Hydroiodic acid(determine ion charges and make sure compound is neutral) A) H$_{2}$I$_{2}$. B) H$_{1}$I$_{1}$. C) HI. D) None of the above. Show Answer Correct Answer: C) HI. 25. What is the name of a chemical, that changes colour in different pH solutions? A) Acid. B) Alkali. C) Water. D) Indicator. Show Answer Correct Answer: D) Indicator. ← PreviousNext →Related QuizzesClass 7 Science Chapter 4 Bases Quiz 1Class 7 Science Chapter 4 Bases Quiz 2Class 7 Science Chapter 4 Bases Quiz 3Class 7 Science Chapter 4 Bases Quiz 4Class 7 Science Chapter 4 Bases Quiz 5Class 7 Science Chapter 4 Bases Quiz 6Class 7 Science Chapter 4 Bases Quiz 7Class 7 Science Chapter 4 Bases Quiz 8Class 7 Science Chapter 4 Bases Quiz 9Class 7 Science Chapter 4 Bases Quiz 10 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books