Chapter 6

Question 1

using more digits than necessary for precision is misleading in that it-

Answer 1

ascribes more accuracy to the determination than is actually the case

Question 2

significant figures are known as-

Answer 2

digits in a number that are needed to express the precision of a measurement from which numbers are derived

Question 3

used as the accuracy of the final result-

Answer 3

take the accuracy of the least accurate measurement, or the measurement with the least number of significant figures

Question 4

Test results sometimes produce-

Answer 4

insignificant digits

Question 5

It is then necessary to round off the numbers to a chosen number of significant value so as not to imply-

Answer 5

an accuracy of precision greater than the test is capable of delivering

Question 6

Exponents are used to indicate-

Answer 6

that a number must be multiplied by itself as many times as indicated by the exponent

Question 7

The exponent is written as a small superscript figure to the immediate right of the base figure and can be called-

Answer 7

the power of the base

Question 8

density-

Answer 8

amount of matter per unit volume of a substance

Question 9

specific gravity-

Answer 9

the weight of 1 mL of a solution compared with the weight of 1 mL of pure water at 4°C

Question 10

Specific gravity multiplied by percent assay equals-

Answer 10

grams of compound per milliliter

Question 11

Concentrated hydrochloric acid (HCl) has a specific gravity of-

Answer 11

1.25 grams per mL (g/mL)

Question 12

Concentrated hydrochloric acid (HCl) has an assay value of-

Answer 12

38%

Question 13

Solutions are made up of-

Answer 13

a mixture of substances

Question 14

Making up a solution usually involves two main parts-

Answer 14

-the substance that is being dissolved (the solute)
-the substance into which the solute is being dissolved (the solvent

Question 15

In working with solutions, it is necessary to know or be able to measure the relative amounts of-

Answer 15

the substance in solution, known as the concentration of the solution

Question 16

Concentration is the amount of one substance relative to-

Answer 16

the amounts of the other substances in the solution

Question 17

a standard Weight (Mass) per unit volume
solution is usually expressed as-

Answer 17

milligrams per milliliter (mg/mL)

Question 18

molality-

Answer 18

the number of moles of solute per kilogram of solvent

Question 19

molarity-

Answer 19

gram-molecular mass (or weight) of a compound per liter of solution

Question 20

millimolarity-

Answer 20

A milligram molecular weight (the molecular weight expressed in milligrams) (mmole).

Question 21

Both osmolality and osmolarity are defined in terms of-

Answer 21

osmoles

Question 22

osmole-

Answer 22

unit of measurement that describes the number of moles of a compound that contribute to the osmotic pressure of a chemical solution

Question 23

osmolality-

Answer 23

the number of osmoles of solute per kilogram of solvent

Question 24

osmolarity-

Answer 24

the number of osmoles of solute per liter of solution

Question 25

Proportions are used to determine-

Answer 25

a quantity from a given ratio

Question 26

ratio-

Answer 26

an amount of something compared to an amount of something else

Question 27

Ratios always describe-

Answer 27

a relative amount, and at least two values are always involved

Question 28

In setting up ratio and proportion problems-

Answer 28

two ratios being compared must be written in the same order, and they must be in the same units

Question 29

a basic relationship or ratio is used to-

Answer 29

relate different concentrations of solutions that contain the same amount of substance (or solute)

Question 30

The volume of one solution (V1) times the concentration of that solution (C1) equals-

Answer 30

the volume of the second solution (V2) times the concentration of the second solution (C2)

Question 31

dilutions-

Answer 31

It is often necessary to make dilutions of specimens being analyzed or to make weaker solutions from stronger solutions

Question 32

dilution is an expression of concentration and refers to-

Answer 32

the volume or number of parts of the substance to be diluted in the total volume, or parts, of the final solution

Question 33

single dilutions calculate the concentration of-

Answer 33

a single dilution

Question 34

Serial dilutions are a dilution series in which-

Answer 34

all dilutions, including or following the first one, are the same

Question 35

serial dilutions are calculation of the concentration after-

Answer 35

a series of dilutions

Question 36

A standard solution is one that contains-

Answer 36

a known exact amount of the substance being measured

Question 37

working standards are prepared from-

Answer 37

stock solution

Question 38

blank solution contains reagents used in-

Answer 38

the procedure, but it does not contain the substance to be measured