This quiz works best with JavaScript enabled. Home > Cbse > Class 7 > Science > Bases > Class 7 Science Chapter 4 Bases – Quiz 9 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 7 Science Chapter 4 Bases Quiz 9 (60 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. Cystosine is always paired with ..... A) Guanine. B) It doesn't match with anything. C) Thymine. D) Adenine. Show Answer Correct Answer: A) Guanine. 2. Which of the following is an Arrhenius Acid? A) H$_{3}$PO$_{4}$. B) CO$_{3}$$^{2-}$. C) Any otheruce. D) OH$^{-}$. Show Answer Correct Answer: A) H$_{3}$PO$_{4}$. 3. A solution has a pH of 6.2, if its hydrogen ion concentration is increased by 10 times, what would its new pH be? A) 8.2. B) 7.2. C) 5.2. D) 4.2. Show Answer Correct Answer: C) 5.2. 4. A type of chemical that forms solutions that taste sour, due to high concentrations of positive hydrogen ions A) PH. B) Acid. C) Salt. D) Base. Show Answer Correct Answer: B) Acid. 5. If a DNA strand has the sequence ATCG, what is the sequence of the complementary strand? A) ATCG. B) CGAT. C) Tagc. D) Cat. Show Answer Correct Answer: C) Tagc. 6. Characteristics such as a widow's peak or attached earlobes are determined by the genetic code. Which components of DNA are referred to as the genetic code? A) Nitrogenous bases. B) Deoxyribose sugars. C) Hydrogen bonds. D) Phosphate groups. Show Answer Correct Answer: A) Nitrogenous bases. 7. Phenolphthalein indicates ..... ? A) Strong Acid. B) Watermelon. C) Strong Base. D) Neutral. Show Answer Correct Answer: C) Strong Base. 8. Cuoh is a name base: A) Copper hydroxide. B) Copper hydroxide I. C) Copper hydroxide II. D) None of the above. Show Answer Correct Answer: B) Copper hydroxide I. 9. What does the Latin root bene mean? A) To carry. B) Good. C) To build. D) Shape. Show Answer Correct Answer: B) Good. 10. Formed when bases react with acids A) Acid. B) Base. C) Neutral. D) None of the above. Show Answer Correct Answer: C) Neutral. 11. What ions are there more of in acidic solutions? A) H+ (H3O+). B) OH-. C) All the above. D) None of the above. Show Answer Correct Answer: A) H+ (H3O+). 12. What are the products to a neutralization reaction? A) H$_{2}$O + Ionic Salt. B) H$_{3}$O$^{+}$ + Ionic Salt. C) OH$^{-}$ + Ionic Salt. D) H$_{2}$ + Ionic Salt. Show Answer Correct Answer: A) H$_{2}$O + Ionic Salt. 13. What does the Latin root contra/counter mean? A) Shape. B) Strength. C) Against. D) To do. Show Answer Correct Answer: C) Against. 14. What is the relational model? A) It is the one that consists of a set of one or more tables that is structured in records and fields that are related to each other. B) It is the one that consists of a set of one or more tables that are structured. C) It is the one that consists of a set of one or more tables that are structured with many. D) It is the one that consists of a set that relates to anyone. Show Answer Correct Answer: A) It is the one that consists of a set of one or more tables that is structured in records and fields that are related to each other. 15. Which is the best definition of a root word? A) An affix which is placed before the stem of a word. B) Word parts that come before or after the stem of a word. C) A basic word or word part upon which prefixes and suffixes can be added to make new words. D) An affix which is placed after the stem of a word. Show Answer Correct Answer: C) A basic word or word part upon which prefixes and suffixes can be added to make new words. 16. Astudenttookahalf-filledtesttubewithdilutehydrochloricacidandafewdropsof phenolphthaleininthesolution.Asheputafewdropsofsodiumhydroxideintothesolution, it turnstolightpink.Further, heputafewextradropsoftheacidandobservesthatthecolour disappears.Whatcausedthecolourtodisappearfromthesolution? A) Thevolumeofthesolutionincreased. B) Turningofthemixtureintoaneutralsolution. C) Decreaseintheamountofacidinthesolution. D) Anincreaseintheamountofbaseinthesolution. Show Answer Correct Answer: B) Turningofthemixtureintoaneutralsolution. 17. What base pairs with guanine? A) Sugar. B) Guanine. C) Thymine. D) Cytosine. Show Answer Correct Answer: D) Cytosine. 18. The formula for hydrochloric acid is ..... A) HCl. B) HSO $ _ {4} $. C) H$_{2}$Cl. D) H$_{2}$SO$_{4}$. Show Answer Correct Answer: A) HCl. 19. What does the Latin root form mean? A) Water. B) Both. C) Shape. D) Square. Show Answer Correct Answer: C) Shape. 20. Given that 43$_{5 }$< x$_{10 }$< 34$_{8, }$which of the following is not a possible value of x? A) 27. B) 25. C) 28. D) 26. Show Answer Correct Answer: C) 28. 21. Determine whether the following substance is an acid or a base:Blood A) Acid. B) Base. C) All the above. D) None of the above. Show Answer Correct Answer: B) Base. 22. What is the Latin root of the word multimedia? A) Media. B) Multi. C) Multiply. D) Multiple. Show Answer Correct Answer: B) Multi. 23. If the pH of a solution is 5.6 the pOH is A) 6.5. B) 5.6. C) 8.4. D) 12.4. Show Answer Correct Answer: C) 8.4. 24. What is DNA made of? A) Phosphate, Nitrogen, Adenine. B) Thymine, Adenine, Cytomine. C) Sugar, Phosphate, nitrogen base. D) Phosphate, Adenine, nitrogen base. Show Answer Correct Answer: C) Sugar, Phosphate, nitrogen base. 25. The vehicle element within the databases is: A) Entity. B) Attribute. C) Valor. D) None of the above. Show Answer Correct Answer: A) Entity. 26. If a substance tastes sour it is known as A) Basic. B) Acidic. C) Neutral. D) None of these. Show Answer Correct Answer: B) Acidic. 27. Which nitrogen base is a purine? A) Adenine. B) Thymine. C) Cytosine. D) Uracil. Show Answer Correct Answer: A) Adenine. 28. Identify the cardinality of the statement:a person has only one nationality but the same nationality can be shared by several people. A) One by one. B) One to many. C) Many to many. D) None of the above. Show Answer Correct Answer: B) One to many. 29. They are the characteristics or properties of an entity. A) ATRIBUTO. B) ENTITY. C) RELATIONSHIP. D) NONE. Show Answer Correct Answer: A) ATRIBUTO. 30. Which of the following is a strong base? A) NH$_{3}$. B) HCl. C) CsOH. D) Zn(OH)$_{2}$. Show Answer Correct Answer: C) CsOH. 31. What type of arrow is used to express a weak acid? A) $\rightarrow$. B) < . C) <$\rightarrow$. D) None of these. Show Answer Correct Answer: C) <$\rightarrow$. 32. We can make natural indicators from these, except A) Water. B) Turmeric. C) Red cabbage. D) Hibiscus flower. Show Answer Correct Answer: A) Water. 33. When Sally tested an unknown solution, her red litmus paper turned blue, but her blue litmus paper remained blue. What does this indicate? A) Unknown is acidic. B) Unknown is neutral. C) Unknown is alkaline. D) Unknown can be acidic, alkaline or neutral. Show Answer Correct Answer: C) Unknown is alkaline. 34. Which of the following is a purine base in DNA? A) Adenine. B) Cytosine. C) Uracil. D) Thymine. Show Answer Correct Answer: A) Adenine. 35. If the H$^{+}$ of a solution is 9.1 x 10$^{-3}$, what is the pH? A) 2.0. B) 12. C) 11. D) 3.0. Show Answer Correct Answer: A) 2.0. 36. 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-. 37. 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}$. 38. 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. 39. 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. 40. 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) 40. B) 4. C) 10. D) 7. Show Answer Correct Answer: D) 7. 41. In a titration experiment, what is the purpose of using an indicator? A) To measure the temperature change. B) To neutralize the acid. C) To increase the reaction rate. D) To determine the endpoint of the reaction. Show Answer Correct Answer: D) To determine the endpoint of the reaction. 42. 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. 43. A pH of 8-14 is a(n) ..... ? A) Neutral. B) Base. C) Phenolphthalein. D) Acid. Show Answer Correct Answer: B) Base. 44. Which of the following latin roots means to say? A) Spec. B) Vis. C) Dict. D) With. Show Answer Correct Answer: C) Dict. 45. What PH number would be an example of a mild base? A) 1. B) 5. C) 9. D) 14. Show Answer Correct Answer: C) 9. 46. What is the name of Mg(OH)$_{2}$ A) Hydromagnesium acid. B) Magnesium hydroxide acid. C) Magnesium hydroxide. D) Magnesium oxygen hydride. Show Answer Correct Answer: C) Magnesium hydroxide. 47. Acid:substance that in solution releases the hydrogen ions (H $^{+1} $) that it possesses. A) REACCIONES DE ACIDO. B) Theoria de bronsted. C) N.A. D) Arrhenius Theory. Show Answer Correct Answer: D) Arrhenius Theory. 48. Nucleotides contain each of the following except: A) Nitrogen base. B) Pentose sugar. C) Glycerol. D) Phosphate. Show Answer Correct Answer: C) Glycerol. 49. 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. 50. CO$_{3}$$^{2-}$(aq)+H$_{2}$O(l) $\rightarrow$ HCO$_{3}$$^{-}$(aq)+OH$^{-}$(aq)Using the above reaction, which compound is the conjugate base? A) H$_{2}$O. B) CO$_{3}$$^{2-}$. C) OH$^{-}$. D) HCO$_{3}$$^{-}$. Show Answer Correct Answer: C) OH$^{-}$. 51. Which of these formulas represents a base A) HNO$_{3}$. B) HF. C) HBr. D) Any otheruce. Show Answer Correct Answer: D) Any otheruce. 52. State all digits that used in base 4. A) 0, 1, 2, 3. B) 0, 1, 2. C) 1, 2, 3. D) 0, 1, 2, 3, 4. Show Answer Correct Answer: A) 0, 1, 2, 3. 53. Select the formula for the following acid:hydroiodic acid A) This $ _ {4} $. B) HI. C) This $ _ {3} $. D) H$_{2}$I. Show Answer Correct Answer: B) HI. 54. Solve 3$^{26}$ = 3$^{4x + 2}$ A) X =-4. B) X = 6. C) X = 5. D) X = 3. Show Answer Correct Answer: B) X = 6. 55. Which of the following bases is commonly used in soap making? A) Sodium hydroxide. B) Ammonium hydroxide. C) Calcium hydroxide. D) Barium hydroxide. Show Answer Correct Answer: A) Sodium hydroxide. 56. 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. 57. 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. 58. Convert 145 to base 4. A) 2101$_{4}$. B) 3001$_{4}$. C) 1202$_{4}$. D) 145$_{4}$. Show Answer Correct Answer: A) 2101$_{4}$. 59. Which of the following base absorbs Carbon dioxide (CO$_{2}$) A) KOH. B) CuSO $ _ {4} $. C) NaoH. D) Mg(OH)$_{2}$. Show Answer Correct Answer: A) KOH. 60. What is the value of digit 2, in base ten, in the number 4231$_{5}$? A) 50. B) 250. C) 200. D) 100. Show Answer Correct Answer: A) 50. ← PreviousNext →Related QuizzesScience QuizzesClass 7 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 8 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books