Chemistry I First Exam

Front 1

Atoms

Back 1

composed of protons (nucleus-positive) neutrons (neutral charge-nucleus) and electrons (orbitals-positive)

Front 2

Protons/Neutrons/Electrons

Back 2

Protons - number of protons represent the atomic number of an element.

Neutrons- change in the number of neutrons results in different isotopes

Electrons- orbitals, changes in the number of electrons results in different ions.

Front 3

Ionic Bonds

Back 3

donation of valence electrons from one atom to another, occurs when electronegativity values of two atoms are different

Front 4

Covalent Bonds

Back 4

sharing of valence electrons between atoms, occurs when electronegativity values are similar

Front 5

Polar and Non-Polar Covalent Bonds

Back 5

Polar Covalent - electrons are unequally shared between atoms

Non-Polar Covalent - electrons are equally shared between the atoms

Front 6

Avogadro's Number

Back 6

6.02x10^23 represents the number of atoms found in 12 grams of carbon 12, one mole.

Front 7

Mole

Back 7

standardized unit of measurement used to practically measure small amounts of chemicals

Front 8

What is Chemistry?

Back 8

study of matter and energy and the interactions between them, it focuses on the properties of substances

Front 9

Physical States

Back 9

solid - fixed shape and volume, liquid - fixed volume/conforms to shape of container/horizontal top surface, gas - takes shape and volume of container

Front 10

Matter

Back 10

has mass and weight, occupies space

Front 11

Mass vs. Weight

Back 11

Mass - the amount of matter something contains, unlike weight it doesn't vary with the objects location

Weight - the pull of gravity on an object, varies with the object's location.

Front 12

Scientific Method

Back 12

Experiment - Results - Hypothesis - Theory

Front 13

Law of Conservation of Mass

Back 13

the sum of the masses of the reactants equals the sum of the masses of the products

Front 14

Extensive Properties

Back 14

depends on the specific sample (mass and weight)

Front 15

Intensive Properties

Back 15

identical in all samples (color, density, melting point)

Front 16

Physical Properties

Back 16

can be observed without changing the substances present in the substance

Front 17

Chemical Reaction

Back 17

reactants undergo chemical change to yield products

Front 18

Reaction Indications

Back 18

evolution of a gas, change of color, formation of precipitate

Front 19

Law of Definite Proportions

Back 19

ALL samples of the same pure substance always contain the same elements in the same proportions by weight.

Front 20

Pure Substances

Back 20

Elements - simplest substances
Compounds - made up of elements

Front 21

Mixtures

Back 21

Heterogenous - uneven texture
Homogenous - solution, sample uniform throughout

Front 22

Separation of Mixtures

Back 22

Filtration - utilize melting point, fractional crystallization, mechanical means)
Distillation - occurs due to differences in boiling point (separation of water and alcohol occur in a fractioning column)
Chromatography

Front 23

Scales

Back 23

Fahrenheit - most common
Rankin - F sized degrees, absolute scale

Celsius - other common scale
Kelvin - C sized degrees, absolute scale

Front 24

Density

Back 24

mass/unit vol.

Front 25

Mass

Back 25

volume x density

Front 26

Volume

Back 26

mass / density

Front 27

Measured Numbers

Back 27

numbers obtained by using tools

Front 28

Exact Numbers

Back 28

not obtained by tools, obtained by definitions or counting.

Front 29

Atomic #

Back 29

is equal to the # of p+

Front 30

Number of Protons

Back 30

all atoms of an element have the same # of p+

Front 31

Charge of Atoms

Back 31

atoms have a zero net charge, they are neutral

Front 32

Number of Electrons

Back 32

is equal to the number of protons in an atom, hence the atomic number not only gives the number of protons but also the number of electrons

Front 33

Isotopes

Back 33

are two atoms with the same number of p+ but a different number of n

Front 34

Atomic Mass Determination

Back 34

atomic mass is determined by the weighted average mass of all the atom's isotopes.

Front 35

Atoms are...

Back 35

can exist alone or enter into chemical combination, they are the smallest indivisible particle of an element.

Front 36

Molecules are...

Back 36

a combination of atoms that has its own characteristic set of properties

Front 37

Law of Constant Composition

Back 37

a chemical compound always contains the same elements, in the same proportions, by mass

Front 38

Law of Multiple Proportions

Back 38

the same elements can be combined to form different compounds by combining the elements in different proportions

Front 39

Dalton's Postulate # 1

Back 39

an element is composed of tiny particles called atoms, all atoms of a given element share the same chemical properties

Front 40

Dalton's Postulate # 2

Back 40

atoms of different elements have different properties

Front 41

Dalton's Postulate # 3

Back 41

compounds are formed when atoms of 2 or more elements combine, in a given compound the relative number of atoms of each kind are definite and constant

Front 42

Dalton's Postulate # 4

Back 42

in an ordinary chemical reaction, no atom of any element disappears or is changed into an atom of another element, chemical reactions involve changing the way in which to atoms are joined together

Front 43

Alpha Radiation

Back 43

two protons and two neutrons, thus a Helium-4 nucleus, possesses a +2 charge and a mass of 4 amu, creates an element with an atomic # of 2 or lower. Ra222 -> Rn222 + He4 (alpha)

Front 44

Beta Radiation

Back 44

high energy electron which was ejected from nucleus, "neutron" converted to "proton", very little mass, -1 charge, creates element with atomic number 1

Front 45

Gamma Radiation

Back 45

nucleus has energy levels, energy released from nucleus as it changes from higher to lower energy levels, it has no mass and no charge.

Front 46

Thompson's Mass to Charge Ratio

Back 46

2 particles with the same mass to charge ratio move in the same path in a vacuum when subjected to the same electric and magnetic fields

Front 47

Millikins Oil Drop Experiment

Back 47

1909- entailed balancing the downward gravitational charge and the upward electric and buoyant forces on charged oil droplets suspended between two metal electrodes established the charge for a single electron 1.602 x 10^-19.

Front 48

Rutherford's Gold Foil

Back 48

alpha particle beam was directed onto a sheet of gold surrounded by zinc sulfide (indicator, glowed when struck by alpha particles). the alpha particles bounced off the atoms at angles less than 90 degrees, availing the fact that a dense object was in the center of the atoms.

Front 49

Rutherford's Atomic Model

Back 49

atoms are composed mostly of vacant space, all the positive charge, and most of the mass, are in a small central area called the nucleus, electrons are in the electron cloud surrounding the nucleus.

Front 50

Proton Charge and Mass

Back 50

found in nucleus, relative mass of 1.0073 amu, charge of +1

Front 51

Neutron Charge and Mass

Back 51

found in nucleus, relative mass of 1.0087 amu, neutral charge

Front 52

Electron Charge and Mass

Back 52

found in the electron cloud, relative mass of .00055, charge of -1

Front 53

If the Nucleus were 1" in diameter...

Back 53

the atom would be 1.5 miles in diameter

Front 54

Cations

Back 54

positive ions

Front 55

Anions

Back 55

negative ions

Front 56

Ionic Compounds

Back 56

combo of cations and anions

Front 57

Z Number

Back 57

number of protons in the nucleus, the number of electrons in a neutral atom, the integer on the periodic table for each element

Front 58

Mass Number

Back 58

integer representing the approximate mass of an atom, equal to the sum of the number of p+ and n in the nucleus

Front 59

H-2 Deuterium

Back 59

one proton and one neutron

Front 60

H-3 Tritium

Back 60

one proton and two neutrons

Front 61

Natural Atomic Mass

Back 61

natural atomic mass = sum [(atomic mass of isotope) x (fractional abundance)]

Front 62

Period

Back 62

horizontal row on the periodic table

Front 63

Group

Back 63

vertical column on the periodic table

Front 64

Group IA

Back 64

alkali metals

Front 65

Group IIA

Back 65

alkaline earth metals

Front 66

Group VIIA

Back 66

halogens

Front 67

Group VIIIA

Back 67

noble gases

Front 68

Types of Elements

Back 68

metals, non-metals, metalloids-semimetals

Front 69

Ionic Bonding - characteristics

Back 69

non-volatile, thus high melting points, solids do not conduct electricity, liquid state will, many (but not all) are water soluble

Front 70

Celsius to Fahrenheit

Back 70

(1.8 x C) + 32 = F

Front 71

Fahrenheit to Celsius

Back 71

.55 x (F - 32) = C

Front 72

Celsius to Kelvin

Back 72

C + 273.15

Front 73

Kelvin to Fahrenheit

Back 73

Convert K to C then C to F

Front 74

Boiling Point of Water

Back 74

373K
100C
212F

Front 75

Room Temperature

Back 75

293K
20C
68F

Front 76

Body Temperature

Back 76

37C
98.6F

Front 77

Water Freezes @

Back 77

273K
0C
32F

Front 78

Significant Numbers

Back 78

ALL Non Zeros
Zeros between Non Zeros
Zeros to the right of the Non Zeros and to the right of the decimal

Front 79

Separation of Matter

Back 79

Matter is either Hetero- or Homogenous. Heterogenous matter can be separated into Homogenous matter. Homogenous matter combines to form solutions. Solutions can be separated into pure substances, that is, compounds or elements. Elements combine to form compounds which can be separated back into elements.

Front 80

Observation

Back 80

a statement that accurately describes something we see, hear, taste, feel or smell

Front 81

Conclusion

Back 81

statement that is based on what we think about a series of observations, "interpretation of the available observations"

Front 82

Data

Back 82

observations we make while performing an experiment

Front 83

Scientific Law

Back 83

a generalization that is uniformly applicable to a host of situations based on the results of many experiments

Front 84

Hypothesis

Back 84

tentative explanation used in the development of a theory

Front 85

Decomposition

Back 85

one substance is changed into two or more substances

Front 86

Number of Elements

Back 86

90 - natural, 27 - man-made

Front 87

Qualitative Observations

Back 87

color, presence of heat, etc. have no numerical value

Front 88

Quantitative Observations

Back 88

measurements, observations that deal with numerical values

Front 89

SI Base Units

Back 89

Length (m) meter
Mass (kg) kilogram
Time (s) second
Electric Current (A) ampere
Temperature (K) Kelvin
Amount of Substance (mol) mole
Luminous Intensity (cd) candela

Front 90

1 amu

Back 90

1.66054 x 10^-27 kg

Front 91

English to Metric - Length

Back 91

1 in. = 2.54 cm
1 yd = .9144 m
1 mi = 1.609 km

Front 92

English to Metric - Mass

Back 92

1 lb = 454 g
1 oz = 28.35 g

Front 93

English to Metric - Volume

Back 93

1 gal = 3.785 L
1 qt = 946.4 ml
1 fl. oz = 29.6 ml

Front 94

Accuracy

Back 94

refers to how close a measurement is to the correct value

Front 95

Precision

Back 95

how closely repeated measurements of a quantity come to each other and to the average

Front 96

Density Mass and Volume Relation

Back 96

D = M/V
M = D * V
V = M/D