Exam 2 CHEM 111

Question 1

Scientific Notation

Answer 1

a method employed to write very small or very large numbers

Question 2

Precision

Answer 2

a measure of how close repeated measurements are to each other

Question 3

Empirical Formula

Answer 3

a formula for a compound that gives the smallest whole-number ratio of each type of atom(EX: C2H4O1)

Question 4

Mass percent composition

Answer 4

the percentage, by mass, of each element in a compound

Question 5

Dimensional Anaylsis

Answer 5

a method to calculate conversions that uses conversion factors stepwise so that units cancel in
each step

Question 6

Kelvin Scale

Answer 6

an absolute temperature scale – the lowest possible temperature is zero

Question 7

Molar Mass

Answer 7

the mass of one mole of an element or compounds

Question 8

Avogadro’s Number

Answer 8

6.022 × 10^23

Question 9

Exact Number

Answer 9

a value that has infinite precision

Question 10

Molecular formula

Answer 10

a formula that gives the exact number of atoms of each element

Question 11

Metric System

Answer 11

the unit system commonly used throughout most of the world, but not in the United States

Question 12

Density

Answer 12

mass/volume

Question 13

Significant Figures

Answer 13

the non-place holding digits in a reported measurement – these digits represent the precision
of the measurement

Question 14

Accuracy

Answer 14

a measure of how close a measurement is to the actual value