chapter 02 True / False Questions 1. Minerals are organic elements extracted from the soil by plants. True False 2. Molecules composed of two or more atoms are called compounds. True False 3. Hydrogen, deuterium, and tritium are three isotopes of hydrogen. True False 4. Potassium, sodium, and chlorine are trace elements. True False 5. Ionic bonds break apart in water more easily than covalent bonds do. True False 6. A solution is a mixture composed of two or more substances that are physically blended but not chemically combined. True False 7. Blood pH is approximately 7.4, which is slightly acidic. True False 8. The high heat capacity of water makes it a very ineffective coolant. True False 9. In an exchange reaction, covalent bonds are broken and new covalent bonds are formed. True False 10. All the chemical reactions in which larger molecules are broken down to smaller ones are called catabolic reactions. True False 11. The opposite of a dehydration synthesis is a hydrolysis. True False 12. Unsaturated fatty acids have as much hydrogen as they can carry. True False 13. A dipeptide is a molecule with two peptide bonds. True False 14. All amino acids have both a carboxyl group and an amino group attached to a central carbon. True False 15. ATP is the body's most important form of long-term energy storage. True False Multiple Choice Questions 16. The most abundant element in the human body, by weight, is A. nitrogen. B. hydrogen. C. carbon. D. oxygen. E. calcium. 17. Sodium has an atomic number of 11 and an atomic mass of 23. Sodium has A. 12 neutrons and 11 protons. B. 12 protons and 11 neutrons. C. 12 electrons and 11 neutrons. D. 12 protons and 11 electrons. E. 12 electrons and 11 protons. 18. The chemical properties of an atom are determined by its A. protons. B. electrons. C. neutrons. D. protons and neutrons. E. particles. 19. Sodium, which has an atomic number of 11, will react with chlorine, which has an atomic number of 17. When these two atoms react, both become stable. To become stable, sodium will ____________, while chlorine will ____________. A. accept one electron; give up one electron B. give up one proton; accept one proton C. share one electron with chlorine; share one electron with sodium D. become an anion; become a cation E. give up one electron; accept one electron 20. Consider oxygen, which has an atomic number of 8 and an atomic mass of 16. How many valence electrons does it have? A. 2 B. 4 C. 6 D. 8 E. 16 21. Oxygen has an atomic number of eight. When two oxygen atoms come together, they form a(n) __________ bond. A. hydrogen B. nonpolar covalent C. polar covalent D. ionic E. Van der Waals 22. When table salt, sodium chloride (NaCl), is placed in water A. Na+ and Cl- form ionic bonds with each other. B. Na+ and Cl- form polar covalent bonds with each other. C. Na+ and Cl- form hydrogen bonds with water. D. Ionic bonds between Na+ and Cl- are broken. E. Na+ and Cl- become separated by their Van der Waals forces. 23. The bonding properties of an atom are determined by its A. electrons. B. protons. C. positrons. D. neutrons. E. photons. 24. What type of bond attracts one water molecule to another? A. an ionic bond B. a peptide bond C. a hydrogen bond D. a covalent bond E. a hydrolytic bond 25. Which of these is a cation? A. O2 B. K C. Na D. Ca2+ E. Cl- 26. ______ account for 98.5% of the body's weight. A. Carbon, oxygen, hydrogen, sodium, potassium, and chlorine B. Carbon, oxygen, iron, sodium, potassium, and chlorine C. Carbon, nitrogen, hydrogen, sodium, potassium, and chlorine D. Carbon, oxygen, hydrogen, nitrogen, sodium, and potassium E. Carbon, oxygen, hydrogen, nitrogen, calcium, and phosphorus 27. Varieties of elements called ________ differ from one another only in number of neutrons and therefore in atomic mass. A. cations B. anions C. isotopes D. electrolytes E. free radicals 28. When you jump off a high diving board into water, you notice great resistance of water. This resistance is called __________ and is caused by water's great ______. A. surface tension; adhesiveness B. surface tension; cohesiveness C. hydrophobic tension; adhesiveness D. hydrophilic tension; cohesiveness E. hydrophilic tension; adhesiveness 29. Which of these is hydrophobic? A. sugar B. K+ C. Cl- D. water E. fat 30. Consider a mixture of blood, which contains sodium chloride, protein, and cells or formed elements. The sodium chloride is in a(n) ____________, the protein is in a(n) __________, and the cells are in a ____________. A. emulsion; solution; suspension B. solvent; emulsion; colloid C. colloid; suspension; solution D. suspension; colloid; solution E. solution; colloid; suspension 31. Which of these is the most appropriate to express number of molecules per volume? A. molarity B. volume C. percentage D. weight per volume E. milliequivalents per liter 32. A solution with pH 4 has ______ the H+ concentration of a solution with pH 8. A. ½ B. twice C. 4 times D. 10,000 times E. 1/10,000 33. Which of these has the highest H+ concentration? A. lemon juice, pH = 2.3 B. red wine, pH = 3.2 C. tomato juice, pH = 4.7 D. saliva, pH = 6.6 E. household ammonia, pH = 10.8 34. Blood has a pH ranging from 7.35 to 7.45. Slight deviations from this can cause major problems, even death. You are doing an intense workout, and your skeletal muscle cells are producing metabolic acids such as lactic acid. Your blood pH does not drop significantly in spite of the metabolic acids released into the blood. You maintain a constant blood pH because A. metabolic acids are neutralized in muscle cells before released into the blood. B. metabolic bases are produced at the same rate by