This quiz works best with JavaScript enabled. Home > Class 7 > Class 7 Science Chapter 4 Bases – Quiz 19 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 7 Science Chapter 4 Bases Quiz 19 (25 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. What is an important safety consideration when handling concentrated alkalis? A) Always add water directly to concentrated alkalis. B) The reaction between alkali and water is exothermic, so care must be taken when adding alkali to water. C) Alkalis should always be mixed with acids. D) Concentrated alkalis can be safely handled without gloves. Show Answer Correct Answer: B) The reaction between alkali and water is exothermic, so care must be taken when adding alkali to water. 2. Alum acts as an antacid. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: B) False. 3. In a BD, objects at a higher level, where information is stored. A) Tables. B) Records. C) Campos. D) Ranks. Show Answer Correct Answer: A) Tables. 4. What are the products when hydrobromic acid is mixed with sodium hydroxide A) H$_{2}$O and NaBr. B) HBr and NaOH. C) OBr and NaH. D) BrOH. Show Answer Correct Answer: A) H$_{2}$O and NaBr. 5. The root phono (from Greek) means "sound." Megaphones are used by cheerleaders, police officers or someone speaking to a large crowd.A telephone lets you hear the voices of people who are far away.If the root "caco" means "bad, " a "cacophonous" piece of music most likely A) Is too quiet to hear clearly. B) Has an upbeat, fast tempo. C) Was written by a bad person. D) Sounds terrible, like screeching cats. Show Answer Correct Answer: D) Sounds terrible, like screeching cats. 6. Acids release ..... A) H$^{+}$. B) OH$^{-}$. C) H$_{2}$. D) None of the above. Show Answer Correct Answer: A) H$^{+}$. 7. What is the formula of calcium oxide? A) CaO. B) Ca $ _ {2} $ o. C) CaO$_{2}$. D) Ca $ _ {2} $ o $ _ {2} $. Show Answer Correct Answer: A) CaO. 8. According to Bronsted-Lowry acid base theory, an acid is a ..... A) Proton donor. B) Proton acceptor. C) Produces H+ when added to water. D) Made of H+. Show Answer Correct Answer: A) Proton donor. 9. Does not react with red litmus paper leaving it red A) Acid. B) Base. C) Neutral. D) None of the above. Show Answer Correct Answer: A) Acid. 10. What is the meaning of the Greek base 'auto'? A) Self. B) Earth. C) Heat. D) Time. Show Answer Correct Answer: A) Self. 11. If there is combined 60% for Cytosine and Guanine, what is the combined % for Adenine and Thymine? A) 60%. B) 40%. C) 20%. D) 10%. Show Answer Correct Answer: B) 40%. 12. Which of the following monomers are repeatedly joined together to form a strand of DNA? A) Amino acids. B) Nucleotides. C) Fatty acids. D) Polysaccharides. Show Answer Correct Answer: B) Nucleotides. 13. The following neutralization reaction occurs in the classroom.HCl + KOH $\rightarrow$ H$_{2}$O + KClIf a student uses 25.0 mL of a 0.5M solution of KOH, what is the molarity of the acid if 15.0mL of acid neutralized? A) 0.8M. B) 1.M. C) 12. D) None of the above. Show Answer Correct Answer: A) 0.8M. 14. A century is ..... years. A) Ten. B) One hundred. C) One thousand. D) Ten thousand. Show Answer Correct Answer: B) One hundred. 15. Which one of the following is NOT a property of acids. A) Tastes sour. B) Corrodes metals. C) Conduct electricity. D) Turns red litmus paper blue. Show Answer Correct Answer: D) Turns red litmus paper blue. 16. What millennium is the year-2465 the year? A) -millennium. B) -millennium. C) -Ier millennium. D) -Ave millennium. Show Answer Correct Answer: A) -millennium. 17. It indicates the relative force, as an acid, for a substance. A) Arrhenius Theory. B) TEORIA DE BRONSTED-LOWRY. C) Hydrogen ion index (pH). D) N.A. Show Answer Correct Answer: C) Hydrogen ion index (pH). 18. Sour taste A) Acid. B) Base. C) Neutral. D) None of the above. Show Answer Correct Answer: A) Acid. 19. A sour taste is a characteristic of: A) Acids. B) Bases. C) Neutral. D) PH scale. Show Answer Correct Answer: A) Acids. 20. The sequence of nitrogenous bases in DNA varies widely. The sequence of the bases in DNA is most important for which of the following? A) Providing the instructions for the traits of an organism. B) Preventing mutations from occuring during RNA replication. C) Allowing the DNA to have the shape necessary for replication. D) Helping form the sugar-phosphate backbone of DNA molecules. Show Answer Correct Answer: A) Providing the instructions for the traits of an organism. 21. Soap A) Base. B) Acid. C) All the above. D) None of the above. Show Answer Correct Answer: A) Base. 22. What century is the year 1769? A) 20th century. B) XVIIth century. C) 21st century. D) 18th century. Show Answer Correct Answer: D) 18th century. 23. PH of 7-14 A) Base. B) Acid. C) All the above. D) None of the above. Show Answer Correct Answer: A) Base. 24. The age element within the databases is: A) Entity. B) Attribute. C) Valor. D) None of the above. Show Answer Correct Answer: B) Attribute. 25. The indicator litmus is added to a solution with a pH of 3.8 what color will it turn? A) Yellow. B) Blue. C) Red. D) Orange. Show Answer Correct Answer: C) Red. ← 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