BIO 2 Multiple choice

20. The characteristic way in which atoms of an element react is most related to the A. number of electrons in the outermost shell. B. number of electrons in the innermost shell. C. number of neutrons in the nucleus. D. size of the nucleus.

A

27. Which term refers to the attraction to water molecules? A. hydrophilic B. hydrophobic C. hydrolysis D. photolysis E. nitrophylic

A

28. Which substances are on the basic side of the pH scale? A. baking soda, oven cleaner and human blood B. baking soda, oven cleaner and urine C. tomatoes, oven cleaner and human blood D. beer, vinegar and black coffee E. Great Salt Lake, oven cleaner, tears

A

29. Which one is NOT one of the properties of water? A. the frozen form is more dense than the liquid form B. the frozen form is less dense than the liquid form C. water is a solvent D. water has a high heat capacity E. water has a high heat of evaporation

A

22. A coastal climate is moderated primarily by which of the following properties of water? Water A. is the universal solvent. B. is cohesive and adhesive. C. has a high heat of evaporation. D. has a high surface tension.

C

25. A solution with a pH of 7.0 has _______ times ________ H+ than a solution of pH 10. A. 30; more B. 300; less C. 103; more D. 10-3; less E. none of these are correct.

C

26. A solution with a pH of 6 has ________ times _________ OH- than a solution with a pH of 10. A. 40; more B. 4000; less C. 104; less D. 4; less E. 104 more

C

21. As a solid, water floats. This means that A. solid water is less dense than liquid water. B. organisms in ponds, lakes, and reservoirs can survive under the ice cover. C. this is due to hydrogen bonding changes. D. All of the choices are correct.

D

23. Human blood has a pH of about 7.4. This is A. neutral. B. very acidic. C. slightly acidic. D. slightly basic.

D

24. Which of the following substances is hydrophilic? A. nonpolar substances B. polar substances C. ionic substances D. both polar and ionic substances E. All of the above are hydrophilic

D

30. Which property of water allows it to act as a transport medium? A. cohesion B. high heat of evaporation C. high heat capacity D. water is solvent E. the frozen form is less dense than the liquid form

D

16. The scale ranges from 1 to 15.

FALSE

15. The scale indicates the relative concentrations of hydrogen and hydroxyl ions in a solution.

TRUE

17. pH 7 has a balanced level of H+ and OH-.

TRUE

18. Anything below pH 7 is acidic and above pH 7 is basic.

TRUE

19. A change of one pH unit represents a ten-fold increase or decrease in hydroxyl ion concentration.

TRUE

1. Which of the following elements would be the most reactive with other elements? A. boron, #5 B. neon, #10 C. argon, #18 D. helium, #2

a

13. Which statement is NOT true about covalent bonds? A. Covalent bonds form when an electron is completely lost or gained from an atom. B. A covalent molecule contains one or more covalent bonds. C. A single covalent bond is drawn as a line between two atoms. D. A pair of electrons is shared between two atoms for each covalent bond. E. Shared electrons allow an atom to complete its outer electron shell in a covalent molecule.

a

6. Which of the following is/are an atom, an isotope and an ion? A. H+ B. 2H or deuterium C. 3H or tritium D. H2 or hydrogen gas E. All of the choices are atoms, isotopes and ions.

a

11. A valence shell is best described as A. the electron shell closest to the nucleus. B. the outermost electron shell of an atom. C. the volume of space in which electrons are most often found. D. the original energy level of electrons in photosynthesis.

b

2. Which of the following would be a proposed mechanism by which stomach antacids work? A. Antacids dilute the solution, therefore lowering the pH. B. Antacids are bases and by definition can absorb H+ out of a solution. C. Antacids are bases and by definition can absorb OH- out of a solution. D. Antacids contain mostly water and so they neutralize the solution.

b

5. If the atomic number of an element is 6 and the atomic mass is 12.01, how many protons are there in the nucleus? A. 12 B. 6 C. 24 D. 52

b

8. Which is NOT true about the electrical charges in chemistry? A. Protons carry a positive charge. B. In an atom, the number of protons and neutrons must be equal. C. An atom is neutral when the positive and negative charges balance. D. An ion contains one or more positive or negative charges.

b

12. Which statement is NOT true about ionic bonds? A. One atom acts as an electron donor and another atom acts as an electron acceptor. B. Electrons are completely lost or gained in ion formation. C. An ion has the same number of electrons as a nonionic atom of the same element. D. An ionic bond occurs between positive ions and negative ions. E. A salt such as NaCl is formed by an ionic reaction.

c

4. Which of the following elements is NOT one of the six most common elements in living organisms? A. carbon B. oxygen C. iron D. nitrogen E. hydrogen

c

10. An atom's atomic mass is best described as the mass of A. the protons it contains. B. the neutrons it contains. C. electrons in the outermost shell. D. protons and neutrons it contains. E. protons and electrons it contains.

d

3. If you place the corner of a paper towel into a droplet of water the water moves across the paper towel. Which of the following would explain the movement of the water? A. surface tension B. cohesion C. adhesion D. both cohesion and adhesion

d

9. In a water molecule, A. the oxygen atom is more electronegative than the hydrogen atoms. B. the oxygen atom has an overall negative charge with the hydrogen atoms having an overall positive charge. C. unequal sharing of electrons results in a polar molecule. D. All of the choices are correct.

d

14. Which statement is NOT true about polar covalent bonds? A. Most covalent bonds are nonpolar, with electrons shared fairly equally between the atoms. B. Polar covalent bonds are important in the characteristics of water. C. Electrons are shared unequally in a polar covalent bond. D. The larger atom in a polar bond attracts the electron more strongly than the smaller atom. E. The oxygen of a water molecule is electropositive relative to the hydrogen.

e

7. Which statement is NOT true about subatomic particles? A. Protons are found in the nucleus. B. Neutrons have no electrical charge. C. Electrons contain much less mass than neutrons. D. Electrons are found in orbitals around the nucleus. E. All electrons in an atom contain the same amount of energy.

e