1.	The element that is combined with oxygen in water is _______________.	

2.	The atomic number is based on the number of ____________.	

3.	A negatively charged particle orbiting the nucleus of an atom is called a ________________.	
4.	An uncharged particle in the nucleus of an atom is a(n) ________________.	

5.	A unit formed by the union of two or more atoms is a(n) ______________.	

6.	A mixture in which the components separate unless shaken is a(n) ________________.	

7.	A substance in which another substance is dissolved is called a(n) ________________.	

8.	The universal solvent is ____________.	

9.	A charged atom or group of atoms is called a(n) ____________.	

10.	A bond formed by the sharing of electrons between elements is called a(n) ________________ bond.	

11.	A negatively charged ion is a(n) ________________.	

12.	Compounds that release ions in solution are called ____________.	

13.	An acid is a substance that donates a(n) ______________ ion to another substance.	

14.	The _________of a solution is based on its concentration of the element hydrogen.	

15.	A substance with a pH of 8.5 is ________________.	

16.	A substance with a pH 4.0 of is ______________ acidic than a substance with a pH of 6.0.	

17.	A form of an element that differs in its atomic weight from other forms of that same element is a(n) ____________.	

18.	The element that is the basis of organic chemistry is ____________.	

19.	All proteins, but not sugars, contain the element ____________.	

20.	A protein that catalyzes reactions is called a(n) ____________.	

21.	The prefix poly– means _______________.	

22.	An element found in table salt is	
A)	chlorine	
B)	hydrogen	
C)	iron	
D)	carbon	

23.	The element that makes up the greatest percentage by weight in the body is	
A)	nitrogen	
B)	potassium	
C)	oxygen	
D)	sodium	

24.	An element needed to build bones is	
A)	nitrogen	
B)	chlorine	
C)	iron	
D)	calcium	

25.	A subunit of an element is a(n)	
A)	molecule	
B)	compound	
C)	mixture	
D)	atom	

26.	The positively charged particles in the atom nucleus are called	
A)	electrons	
B)	protons	
C)	isotopes	
D)	neutrons	

27.	The atomic number of phosphorus is 15. How many protons does phosphorus have?	
A)	15	
B)	More information is required to answer this question.	
C)	12	
D)	10	

28.	The atomic number of sodium is 11. The sodium ion has a single positive charge (Na+). How many electrons does the sodium ion have?	
A)	11	
B)	12	
C)	More information is required to answer this question.	
D)	10	

29.	A common isotope of sodium is called sodium-24, based on its atomic weight. The atomic weight can be calculated by adding the number of protons and the number of neutrons. The atomic number of sodium is 11. How many neutrons does sodium-24 have?	
A)	11	
B)	More information is required to answer this question.	
C)	9	
D)	13	

30.	Cobalt has 27 electrons. What is its atomic number?	
A)	More information is required to answer this question.	
B)	13	
C)	27	
D)	54	

31.	A combination of two or more substances that are not chemically bonded is a(n)	
A)	atom	
B)	mixture	
C)	compound	
D)	molecule	

32.	A substance composed of two or more different elements participating in a chemical bond is a(n)	
A)	solution	
B)	mixture	
C)	compound	
D)	atom	

33.	A substance that dissolves in another substance is a(n)	
A)	solvent	
B)	mixture	
C)	solute	
D)	solution	

34.	Which of the following is a mixture?	
A)	sodium hydroxide	
B)	sugar water	
C)	table salt	
D)	hydrochloric acid	

35.	A non-separating suspension can be described as	
A)	inorganic	
B)	nuclear	
C)	covalent	
D)	colloidal	

36.	A mixture in which the components remain evenly distributed is a(n)	
A)	compound	
B)	molecule	
C)	suspension	
D)	solution	

37.	A chemical bond formed by the sharing of electrons is described as a(n)	
A)	coordinate bond	
B)	mixture	
C)	ionic bond	
D)	covalent bond	

38.	A graphic tracing of the electric current generated by the heart is called a(n)	
A)	radiotracing	
B)	electroencephalogram	
C)	thallium stress test	
D)	electrocardiogram	

39.	A basic substance could have a pH of	
A)	6	
B)	7	
C)	12	
D)	0	

40.	Which of the following is an organic compound?	
A)	glycerol	
B)	zinc	
C)	water	
D)	salt	

41.	The chemical category that includes fats and cholesterol is	
A)	carbohydrates	
B)	solutions	
C)	lipids	
D)	proteins	

42.	Proteins are complex molecules composed of	
A)	glucose	
B)	water	
C)	amino acids	
D)	calcium	

43.	The simplest form of carbohydrate is	
A)	monosaccharides	
B)	polysaccharides	
C)	unisaccharides	
D)	disaccharides	

44.	All enzymes are	
A)	None of the answers are correct.	
B)	proteins	
C)	lipids	
D)	carbohydrates	

45.	A hydrophobic substance	
A)	repels water	
B)	is a colloid	
C)	contains hydrogen bonds	
D)	mixes easily with water	

46.	A substance that has a name ending in –ase is most likely a(n)	
A)	mixture	
B)	protein	
C)	lipid	
D)	carbohydrate	

47.	List, and briefly describe, two uses of radioisotopes.	

48.	List the three characteristics of organic compounds.	

49.	List and briefly describe the three types of carbohydrates and give an example of each.	

50.	Mr. L has difficulties digesting milk products due to a deficiency in the enzyme lactase. His doctor has provided him with a solution of lactase to consume every time he eats a dairy product. Mr. L decides he wants some hot chocolate. He boils his lactase with his milk to save time. His hot chocolate causes him a severe stomachache, so he calls his doctor to complain. Why did his lactase fail to work?	

51.	Using your knowledge of word parts, what would be a logical definition for the term monosaccharidase?	

Answer Key

1.	hydrogen	
2.	protons	
3.	electron	
4.	neutron	
5.	molecule	
6.	suspension	
7.	solvent	
8.	water	
9.	ion	
10.	covalent	
11.	anion	
12.	electrolytes	
13.	hydrogen	
14.	pH	
15.	basic or alkaline	
16.	more	
17.	isotope	
18.	carbon	
19.	nitrogen	
20.	enzyme	
21.	many	
22.	A	
23.	C	
24.	D	
25.	D	
26.	B	
27.	A	
28.	D	
29.	D	
30.	C	
31.	B	
32.	C	
33.	C	
34.	B	
35.	D	
36.	D	
37.	D	
38.	D	
39.	C	
40.	A	
41.	C	
42.	C	
43.	A	
44.	B	
45.	A	
46.	B	
47.	Radioisotopes are used for cancer (radiation) treatment. The radiation harms tumor cells to a greater extent than normal cells. Radioisotopes are also used for diagnosis. X-rays use radioisotopes. Also, radioisotopes can be taken into the body and used to diagnose tissue abnormalities.	
48.	Organic compounds (1) contain carbon, (2) form large, complex molecules, and (3) are found in living things.	
49.	Monosaccharides are simple sugars consisting of a single sugar residue. An example is glucose. Disaccharides consist of two simple sugars. An example is maltose. Polysaccharides consist of many simple sugars linked together. Examples are starch and glycogen.	
50.	Enzymes are proteins. They are often inactivated by extreme heat. When Mr. L boiled his lactase solution, he inactivated the enzyme.	
51.	Mono means one, sacchar/o means sugar, and –ase signifies an enzyme. A monosaccharidase would thus be an enzyme that acts on simple sugars (monosaccharides).