CHEMISTRY REVIEW Flashcards
REVIEW
1
Q
Matter
A
anything that has mass and takes up space
takes up space means volume
2
Q
Mass
A
the amount of material in a substance, the amount of stuff that’s present and takes up the space
3
Q
describe matter as a solid
A
has definite shape and definite volume
particles are closely packed and rigidly held in fixed positions
4
Q
describe matter as a liquid
A
has no definite shape, but has a definite volume
the particles are not bound in fixed positions and can slide past and around each other
5
Q
describe matter as a gas or vapor
A
has no definite shape and no definite volume
6
Q
occurs when somethin in solid form changes into liquid
A
melting
7
Q
melting point
A
the temperature at which matter changes from a solid to a liquid
8
Q
the change from liquid to solid
A
freezing
9
Q
the temperature at which a liquid changes into a solid
A
freezing point
10
Q
boiling
A
the change from liquid to gas (vapor) at the boiling point
11
Q
evaporation
A
the change from liquid to gas (vapor) below the boiling point
12
Q
the term that describes the change from gas (vapor) to liquid
A
condensation
13
Q
when a liquid, gas, or solid is cooled the molecules
A
lose kinetic energy and slow down
14
Q
increases of kinetic energy and speeds up molecules
A
when a solid, liquid, or gas is heated
15
Q
sublimation
A
the change from a solid directly to a gas (vapor)
dry ice is frozen carbon dioxide
16
Q
Examples of physical properties
A
density, specific gravity, shape, hardness, odor, color, solubility, melting point, and boiling point
17
Q
chemical properties
A
characteristics of matter that allow it to combine or react with other matter
18
Q
Matter can not be created or destroyed
A
Law of Conservation of Mass/Energy
19
Q
two or more pure substances that are physically combined in variable proportions
A
Mixture
20
Q
solution
A
homogeneous mixtures
molecules of the two bonded substances intermix evenly but are not bound together by intermolecular bonds
21
Q
solute
A
the substance in a solution that is dissolved into another substance
ie sugar in water and oxygen in our atmosphere
22
Q
the solution that dissolves the other substance
ie water in our sugar water and nitrogen in our atmosphere
A
solvent
23
Q
solubility
A
refers to how easily a substance will or will not dissolve readily it is said to be soluble.
salt and sugar are soluble in water
silicon dioxide (sand) is insoluble in water
Soluble is means that the compound is able to break apart into fragments too small to be caught by any filter
24
Q
homogeneous sample of matter that has the same composition and properties, whatever its source
A
pure substance
25
compound
pure substances composed of two or more different elements chemically combined in fixed proportions
26
two or more atoms chemically bonded together
the smallest piece of a compound that can exist and keep its properties
molecule
molecules of an element (diatomic)
molecules of an compound
27
the higher the atomic number the more energy levels the atom has, the electrons are further from the nucleus, and more reactive the atom
How the atomic number influences the chemical properties of an atom
28
protons
carries a positive electrical charge in the nucleus
is about 1 amu
give atoms their identity, identifies the element
atomic number
the periodic table is arranged the order of increasing atomic number
29
The two regions of an atom
the nucleus and the electron cloud
30
subatomic particles that reside in the nucleus along with the proton
neutral charge
1amu
neutrons
31
atomic mass number
sum of protons and neutrons in the nucleus
32
Isotopes
Atoms with the same number of protons but different number of neutrons
33
negatively charged subatomic particle
makes up an elements volume through the electron cloud
.0055amu
electron
34
Reactivity for columns 1 and 2
Reactivity for columns 16 and 17
Reactivity for column 18
Increases as you go down the column
Increases as you go up the column
Are unreactive because their valence shell is full
35
valence electron
valence shell
electrons in the highest energy level or electrons in the outermost shell
the outermost shell or the highest energy level
the most chemically active electrons
can also mean ionic charge
36
Why does bonding happen on the outer most electrons
the elements strive to achieve an outer shell that is full of electrons
37
ionization
occurs when electrons are gained or lost by an atom or compound
38
anion
negatively charged ions formed when the atom gains electrons
39
cation
positively charged ions formed when the atom losses electrons
40
period
each row on a periodic table
all the elements have same number of energy shells
41
groups
the columns on a periodic table
they contain the same number of electrons on the valence shell
valence shells have the same electron configuration
42
Number of electrons per shell
The inner or first shell needs 2 electrons to be full
The rest of the shells want 8 electrons
43
The stair step on the periodic table is the ____
These elements have characteristics of metals and non-metals depending on the conditions
Boron, Silicon, Germanium, Arsenic, Antimony, Tellurium, and Polonium
Metalloids
44
Unreactive gasses because their valence shell is full
Inert or Noble Gases
45
In groups one and two the reactive increases going _____ the column
Down
46
First write out chemical notation (think isotopes)
What does he large X represent
The element's symbol
47
First write out chemical notation (think isotopes)
What does the Z represent
The atomic number and the number of protons
48
First write out chemical notation (think isotopes)
What letter represents the mass number
A is the mass number and tells us the number of protons and neutrons
49
First write out chemical notation (think isotopes)
What does the + or - represent
The + or - denotes ionic charge. Charge is based on excess (-) or deficiency (+) of electrons.
50
First write out chemical notation (think isotopes)
How do we denote the number of atoms in the molecule?
The n on the right bottom
51
Atomic weight
the weighted average of the masses of all of the an element's naturally occurring isotopes
52
the sum of the atomic weights of all the atoms in the molecule
molecular weight
53
The mole
is a counting term we use, represents 6.022 x 10^23
54
Gram atomic weight (gaw)
mass (weight) in grams of a mole of atoms
55
formed when electrons are gained and lost
ionic bonds
56
the electrostatic attraction between oppositely charged particles
the force that holds ionic bonds
57
covalent bonding
two atoms share electrons in order to fill their outer shells
58
the force that holds together covalent bonds
are the overlapping (intertwined) electrons clouds of the atoms
59
the bonding in which each atom contributes its valence electrons, these electrons are delocalized, and the valence electrons are shared by many atoms
metallic bonding
60
the purpose of a balanced equation
tells us the amounts of reactants and products involved, number of atoms and molecules, number of moles and mole ratios, or masses
61
the quantity of heat released or absorbed during a chemical reaction
heat of a reaction or delta H
62
exothermic reaction
is when energy is given off or released an example is a burning candle
63
endothermic reaction
when energy is absorbed and example is cooking an egg, baking bread, water evaporation, and melting ice cubes.
64
the minimum amount of energy required to start a chemical reaction
activation energy
65
how rapidly a chemical reaction progresses, and whether the reaction is speeding up or slowing down as it progresses
reaction rate
66
factors that affect reation rate
nature of the reactant- how reactive the react is
surface area- when solids react the chemical reaction takes place on the surface of the solid
concentration- is a measure of how many atoms ore molecules or ions are contained in a given volume of material
temperature
catalyst
67
catalyst
substance that changes the rate of a chemical reaction but doesn't get permanently consumed during the reaction
68
reversible reaction
a reaction in which the products can react to re-form the reactants
69
chemical equilibrium
the state in which the rate of the forward and reverse reauctions are exactly equal
70
shifting the equilibrium
means the reaction is shifted to favor either the forward or the reverse reaction. By adjusting the reaction conditions and quantities of materials, we can shift the equilibrium to reach a more desired state.
71
the state of a solution when it holds the maximum amount of a dissolved substance at a given temperature.
saturation
72
a solution that contains the maximum amount of dissolved solute
saturated solution
73
super saturated solution
a solution that contains more dissolved solute than a saturated solution under the same conditions
74
chemical concentration
concentration in context of a chemical reaction
is a measurement of the amount of solute present in a given amount of solvent or solution.
The total mass of reactants in a given volume of material
75
a solution with a relatively small amount of solute as compared to the amount of solvent
dilute solution
76
the process by which the concentration of solution is increased
concentration process
77
the process by which the concentration of a solution is decreased
dilution process
78
electrolytes
substances that form ions when they dissolve in water
ionic compounds composed of both negative and positive ions
79
compounds that dissolve in water to produce hydrogen ions
acids
80
neutralization
the reaction of hydrogen ions and hydroxide ions to form a salt and water
81
the negative logarithm of the hydrogen ion concentration of a solution
pH
82
pH of a solution grater than 7
basic
83
the pH of a solution is less than 7
acid
84
the pH is equal to 7
neutral
85
Three reasons we treat water
to minimize corrosion
to minimize radiation
to minimize fouling of heat transfer surfaces
86
What happens to corrosion rates of metals when there is impurities
The corrosion rate of metals is increased by impurities. High corrosion rates can lead to the failure of components or systems
87
mixed resin beds filter ___
all dissolved solids
88
IT is important to maintain the proper pH of a water-based system in order to
control the rate of corrosion
89
Deaeration
filtration
ion exchange
Methods to filter water
90
Deaeration
method used to remove or strip dissolved gases from water and vent them into the atmosphere
91
Cation and Anion resin beds can control pH by
cation resin releasing hydrogen ions increasing the pH
anion resin releasing hydroxide ions decreasing the pH
92
Sand
Activated charcoal (treated to increase absorptive power)
anthracite
diatomaceous earth
ion exchanger resin
five common filtration media
93
Agitators are used in ion exchangers
during initial resin loading, after resin replacement, and during resin generation
94
water flows what direction through the ion exchanger (IX)
From top to bottom
95
The bottom port of the Ion Exchanger is used to _____
remove resin beads
96
influent water
waste water, makeup water, water to be filtered
97
pure water, filtered water
effluent water
98
Resin channeling
A condition in which the resin allows a direct flow of water through the ion exchange. Flow channels are established from the inlet to the outlet of the ion exchanger, which allows water to flow essentially unrestricted through the resin via these paths.
99
small particles that may clog the retention elements in the ion exchanger reducing ion exchanger flow
resin fines
100
oxidation-reduction reactions
chemical change that electrons are gained or lost
101
Reduction
is when a chemical gains one or more electrons
102
when a chemical loses one or more electrons
oxidation
103
the surface of a metal undergoes a slow, relatively uniform deterioration and removal of metal
general corrosion
104
the mechanism by which general corrosion occurs is
the metal ionizes, dissolves into solution, and may form other compounds such as metal oxides
105
As temperature changes corrosion changes
As temperature increases corrosion increases
As temperature decreases corrosion decreases
106
Oxygen causes corrosion to
as oxygen increases corrosion increases
as oxygen decreases corrosion decreases
107
metal surface, condition, and composition effect corrosion
Deposits of insoluble impurities and irregular metal surfaces create areas where local corrosion can initiate and proceed at a faster than normal rate. A pitted, uneven surface where these impurities can deposit is more susceptible to corrosion that a polished, flat surface.
108
Protective layer, passivity, and corrosion
Removal of the protective layers will increase the rate of corrosion.
109
Commonly used technique to prevent or slow corrosion
Separate the metal from water in the environment. This can be accomplished by painting the surface or applying a protective coating to the metal surface.
110
The process in which an oxide layer to form between the metal and the environment. This process results in the metal being separated from its environment.
Passivity
111
Iron corrosion can be slowed by two factors
pH and oxygen. If possible, systems containing iron should be operated in the pH range (4-10) that promotes the lowest corrosion rate.
112
Galvanic corrosion
when two dissimilar metals with different potentials are placed in electrical contact in an electrolyte (an electricity conducting fluid)
113
a metal that is more easily oxidized than the metal to be protected (higher on the electromotive series table)
a metal that is more easily oxidized than the metal to be protected
sacrificial anode
114
pitting corrosion
occurs where the corrosion site becomes fixed in a small area and the formation of holes takes place in an otherwise unaffected area.
115
a type of pitting corrosion that occurs specifically within the low flow region of a crevice
crevice corrosion
116
stress corrosion cracking (SCC)
a form of corrosion that can produce spontaneous failure of metals as the result of the combined action of a corrosive environment and tensile (pulling apart) stress
117
Two main ways to reduce stress corrosion cracking
to reduce tensile stresses
to eliminate or reduce severity of the corrosive environment
118
Why is using alternate materials not a great option for reducing stress corrosion cracking
The cost or fabrication difficulties eliminates this option for most applications
119
Tensile stress
type of stress that occurs when a material is being pulled apart, stretched, or elongated
120
the reverse of tensile stress, occurs when a material is being pressed together, compacted or squeezed
compressive
121
exists when two parts of a material are loaded causing them to tend to slide across each other
shear stress
