EXPRESSING QUANTITIES & CONCENTRATIONS

Question 1

Acronym for the French word Systeme International d’ Unites
It is the standardized system of units

Answer 1

SI UNITS

Question 2

Base unit of Length

Answer 2

Meter

Question 3

Base unit of Time

Answer 3

Second

Question 4

Base unit of Mass

Answer 4

Kilogram

Question 5

Base unit of Temperature

Answer 5

Kelvin

Question 6

Base unit of Electric Current

Answer 6

Ampere

Question 7

Base unit of Luminious Intensity/ Light

Answer 7

Candela

Question 8

Base unit of amt. of substance

Answer 8

Mole

Question 9

It is the SI unit for the amount of chemical species
Associated with a chemical formula and Avogado’s number (6.00 x 1023)

Answer 9

The Mole

Question 10

is the mass in grams of one mole of the substance
Calculated by summing the atomic masses of all the elements appearing in a chemical formula

Answer 10

Molar Mass (M)

Question 11

Is an invariant measure of the amount of matter in an object

Answer 11

Mass

Question 12

Is the force of attraction between an object and its surrounding

Answer 12

Weight

Question 13

It is the one thousandth of a mole (1/1000 of a mole)

Answer 13

The Millimole

Question 14

Number of moles of the solute species that is contained in one liter of the solution

Answer 14

Molar Concentration (Molarity M)

Question 15

Is the total number of moles of solute in 1 L of solution

Answer 15

Analytical Molarity

Question 16

AKA species molarity
Molar concentration of a particular species in solution at equilibrium

Answer 16

Equilibrium Molarity

Question 17

Frequently used to express the concentration of commercial aqueous reagent

Answer 17

Weight Percent (w/w)

Question 18

• Commonly used to specify the concentration of a solution prepared by diluting a pure liquid solute with another liquid

Answer 18

Volume Percent (v/v)

Question 19

Often used to indicate the composition of dilute aqueous solution of solid reagents

Answer 19

Weight/Volume Percent (w/v)

Question 20

is the negative logarithm (to the base 10) of the molar concentration of that species. Thus, for the species X

Answer 20

-p-value

Question 21

is the mass of a substance per unit of volume - in SI Units, expressed as kg/L of g/mL

Answer 21

Density

Question 22

Is the ratio of the mass of a substance to the mass of an equal volume of water

Answer 22

Specific Gravity

Question 23

is the quantitative relationship among the amounts of reacting chemical species.

Answer 23

Stoichiometry

Question 24

Used to measure the central value
AKA arithmetic mean or the average

Answer 24

Mean

Question 25

Is the middle result when replicate data are arranged in increasing or decreasing order

Answer 25

Median

Question 26

describes the reproducibility of measurements—in other words, the closeness of results that have been obtained in exactly the same way

Answer 26

Precision

Question 27

indicates the closeness of the measurement to the true or accepted value and is expressed by the error

Answer 27

Accuracy

Question 28

Is the difference between the measured value and the true value

Answer 28

Absolute Error

Question 29

Is the absolute error divided by the true value

Answer 29

Relative Error

Question 30

causes data to be scattered more or less symmetrically around a mean value affects measurement precision

Answer 30

Random Error

Question 31

causes the mean of a data set to differ from the accepted value affects the accuracy of result

Answer 31

Systemic Error -

Question 32

usually occur only occasionally, are often large, and may cause a result to be either high or low

Answer 32

Gross Error (Outlier)

Question 33

is an occasional result in replicate measurements that differs significantly from the other result

Answer 33

outlier

Question 34

TYPES OF ERROR IN EXPERIMENTAL DATA

Answer 34

Random Error Systemic Error Gross Error (Outlier)

Question 35

SOURCES OF SYSTEMIC ERROR

Answer 35

Instrumental Errors Method Errors Personal Error

Question 36

are caused by nonideal instrument behavior, by faulty calibrations, or by use under inappropriate conditions

Answer 36

Instrumental Errors-

Question 37

arise from nonideal chemical or physical behavior of analytical systems

Answer 37

Method Errors

Question 38

result from the carelessness, inattention, or personal limitations of the experimenter

Answer 38

Personal Error

Question 39

are independent of the size of the sample being analyzed

Answer 39

Constant Errors

Question 40

Decrease or increase in proportion to the size of the sample

Answer 40

Proportional Errors

Question 41

If standard samples are not available, a second independent and reliable analytical method can be used in parallel with the method being evaluated - Independent method should differ as much as possible from the one under study

Answer 41

Independent Analysis