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Chemistry 543
Midterm Review 2013
1. Scientific method the logical approach to the solution of scientific problems.
2. Biochemistry the study of the chemistry of living organism.
3. Analytical chemistry branch of chemistry concerned with the composition of substances.
4. Hypothesis an educated guess.
5. Theory a broad and extensively tested explanation of why experiments give certain results.
6. Chemistry the study of the composition of matter and the changes that it undergoes.
7. Experiment the means to test a hypothesis.
8. Observations uses your senses to obtain information directly.
9. Organic chemistry the study of essentially all substances containing carbon.
10. Physical chemistry branch of chemistry concerned with theories and experiments that describe the
behavior of chemicals.
11. Liquid Matter that flows but has a definite volume
12. Mass Amount of matter that an object contains
13. Reactant Starting substances in a chemical reaction
14. Solution a type of homogeneous mixture
15. Element The simplest forms of matter
16. Physical change Alters a substance without changing its chemical composition
17. Solid Matter with a definite shape and volume
18. Product Substances formed in a chemical reaction
19. Matter Anything that takes up space and has mass
20. Iron oxide In the chemical reaction iron + oxygen  iron oxide: What is the product?
21. Three states of matter: solid, liquid and gas
22.
Na
chemical symbol for sodium
23.
Cl
The chemical symbol for chlorine
24. A gas is a form of matter that: takes both the shape and volume of its container, is easy to
compress and has high NRG
25. Homogeneous mixtures are: completely uniform mixture (ie. Coffee, tea, saltwater, etc)
26. Heterogeneous mixtures are: mixture with varied composition (ie. M&M, salad, dirt, etc.)
27. A compound is: a chemical combination of elements, in whole number ratios.
28. List physical properties of a substance:
color, solubility, odor, hardness, density, melting
point, boiling point, texture, compressibility, freezing point
29. When iron and oxygen combine to form iron oxide (rust), is this a Chemical or physical change?
30. During chemical and physical changes, substances absorb or give off heat or NRG.
31. During
32.
distillation , a liquid is boiled to produce a vapor that is then condensed again to a liquid.
Heterogeneous mixtures differ from pure substances because these mixtures are not uniform.
33. When iron and sulfur combine to form iron sulfide, a Chemical change takes place.
34. A Physical property is a quality of a substance that can be observed or measured without
changing the composition of the substance.
35. Elements combine chemically to form compound .
36.
Iron
Fe is the chemical symbol for what element?
37. A homogeneous mixture has a completely uniform composition.
38. In any physical or chemical change, mass is neither created nor destroyed (conserved)
39. In a chemical reaction, the new substances formed are called
products
40.
Weight
A measure of the pull of gravity on a given mass.
41.
Precision
Being able to reproduce a measurement or out come.
42.
Density
The ratio of the mass of an object to its volume.
43.
Error
The difference between the accepted value and the experimental value.
44.
Temperature The degree of hotness or coldness of an object.
45.
Accuracy
The closeness of a measurement to the true value.
46.
Volume
The space occupied by matter.
47. List all the SI units and what they measure
meter – length, cubic meter or Liter – volume,
kilograms – mass, Kelvin – temperature, seconds – time, joule – NRG, pressure - pascal
48.
Quantitative Measurements that have a definite values and numbers are called.
49.
Qualitative
When results are given in a descriptive form, they are called.
50.
5 sig figs.
How many significant figures are in the measurement 2103.2 g?
51.
3 zeros
How many of the zeros in the measurement 0.000 040 200 m are significant
(should be counted)?
52.
3 sig figs.
How many significant figures are in 2.50 kg?
53.
Accuracy
The closeness of a measurement to its true value is a measure of its:
54. List three measurements in which the number is expressed to three significant figures.
Answers will vary
examples are
55. List the metric prefixes and their values
100.
114
0.00300
Giga 1 x 109, Mega 1 x 106, kilo 1 x 103, base 1 x 100,
deci 1 x 10-1, centi 1 x 10-2, milli 1 x 10-3,micro 1 x 10-6, nano 1 x 10-9, pico 1 x 10-12
56. What is the formula for density?
D = mass/volume
57. What is the volume of 60.0 g of ether if the density of ether is 0.70 g/mL?
V = mass
=
volume
60.00g
= 85.7 mL
0.70 g/mL
85.7 mL
58. What is the formula for converting from Celsius to Kelvin?
°C + 273 = K
59. What is the formula for converting from Kelvin to Celsius?
K – 273 = °C
60. An acid has a density of 1.19 g/mL. What is the mass, in grams, of 2000 mL of this acid?
Mass = density x volume = 1.19 g/mL x 2000 mL = 2380 g
2380 g
61. What is the mass, in grams, of 1000.0 cm3 of balsa wood if the density is 0.20 g/cm3 ?
Mass = density x volume = 0.20 g/cm3 x 1000.0 cm3 = 200 g
200 g
62. Chlorine boils at 239 K. What is the boiling point of chlorine expressed in degrees Celsius?
K – 273 = °C
239 K – 273 = -34°C
-34°C
63.
Mass number
The total number of protons and neutrons in the nucleus of an atom
64.
Atomic mass The weighted average mass of the atoms in a naturally occurring sample of an
element
65.
Atomic mass unit
One-twelfth the mass of a carbon-12 atom
66.
Atomic number
The number of protons in the nucleus of an element
67.
Isotopes
Atoms with the same number of protons but different numbers of neutrons
68.
electrons
Negatively charged subatomic particles
69.
Atom The smallest particle of an element that retains the properties of that element.
70.
Neutron
Subatomic particle with no charge
71.
Protron
Positively charged subatomic particles
72. The nucleus of an atom is:
a hard core, positively charged center of an atom
73. Dalton theorized that atoms are indivisible and that all atoms of an element are identical.
Scientists now know that:
atoms can be divided, contain subatomic particles and are not all
alike (isotopes)
74. The number of neutrons in the nucleus of an atom can be calculated by:
Mass number – Atomic number
75. All atoms of the same element have the same:
the same number of protons & properties
76.
Noble gases These elements are found in Group 0.
77.
JJ Thomson Who came up with the “plum pudding” model of the atom?
78.
Ernest Rutherford
Who discovered the nucleus?
79. The periodic law states that:
when elements are arranged in order of increasing atomic
number, there is a periodic repetition of their physical and chemical properties.
80.
Amu’s (atomic mass units) Relative atomic masses are measured in:
81.
Mendeleev
82.
Atomic emission spectra or line spectra Lines of colored light obtained by passing the light
He got credit over Meyers for the first periodic table.
emitted by an element through a prism
83.
NRG level
The region around an atomic nucleus where an electron is likely to be moving
84.
spectrum
A range of colors seen when light passes through a prism
85.
Aufbau principle
Rule/Law that states that electrons enter orbitals of lowest energy first.
86.
Atomic orbital
A region outside the nucleus where there is high probability of finding an
electron
87.
3 orbitals
The p sublevel has how many orbitals:
88.
chlorine
If the electron configuration of an element is 1s2 2s2 2p6 3s2 3p5, name the
element .
89.
18
The maximum number of electrons that can occupy the third principal energy level is:
90.
NRG level
In the formula 2p6, the 2 represents:
91. In order to occupy the same orbital, two electrons must have:
opposite spins
92. According to Hund’s rule, when electrons occupy orbitals of equal energy, one electron enters
each orbit until:
each contain 1 electron with parallel spins, then the second electron is added in
opposite spin
93. Identify the elements that have the following electron configurations:
a. 1s2 2s2 2p6 3s2 3p1
Al
b. 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6
Kr
c. 1s2 2s2 2p6 3s2 3p6 4s2 3d7
Co
94. Consider the elements neon, bromine, and phosphorus. Which has:
a. three electrons in its 3p sublevel?
Phosphorus
b. its highest energy level completely filled?
Neon
c. the highest occupied energy level?
Bromine
95.
Transition metal
An element whose outermost s or d sublevels are only partially filled.
96.
Ionization NRG
The NRG needed to remove an electron from a gaseous atom
97.
Period
98.
Valence electrons
99.
Halogen
100.
A horizontal row on the periodic table
The electrons in the outermost NRG level are called
Any of a family of nonmetals including fluorine and chlorine are called
Electronegativity
The tendency of an atom to attract electrons to itself when it is
chemically combined with another element
101.
Noble gases
An element in which the outermost s and p sublevels are completely filled
102.
Inner transition Metals
An element found in the f block.
103.
d block
104.
Group A elements The representative elements are usually called:
105.
Group or Family
106.
s-orbital (5s) When a strontium atom loses two electrons to form a Sr2+ ion, the
Which orbital corresponds to the transition metals in the periodic table?
The vertical columns of the periodic table are called:
electrons are lost from which orbital?
107.
The element iodine, I, is what type of element:
period:
108.
Group
7A
Period
5
How many diatomic elements are there?
Halogen
, found in which group and
,
7
Name all of them. Hydrogen, oxygen,
nitrogen and the halogens (except At too radioactive)
109.
Electron
The subatomic particle that plays the greatest role in determining the
physical and chemical properties of an element is the:
110.
Which of the following atoms would you expect to have the largest atomic radius?
a. I
b. Na
111.
Fluorine
112.
Transition Metals
113.
c. Ca
d. Sr
Which element is the most electronegative:
Group B elements are also known as the
How do you determine the atomic radius of an element?
Measure the distance between 2
nuclei and then divide by two.
114.
A polyatomic anion consists of is a tightly bound group of atoms that behave as a unit and
carry a negative charge.
115.
8 dots
In the Lewis Dot Structure, what is the maximum number of dots that can
be used?
116.
Write Lewis Dot Structures for all the elements in Period 2 of the Periodic Table
Li
Be
117.
A metallic bond is a bond between:
B
C
N
O
F
Ne
the force of attraction that holds the metals together, it
consists of free floating valence electrons and the positively charged metal ions
118.
What is meant by one lone pair of electrons?
Unshared pair of electrons
119.
Know the number of valence electrons found in each group of the Representative elements
1A = 1, 2A = 2, 3A = 3, 4A = 4, 5A = 5, 6A = 6, 7A = 7 and 0 = 8
120.
In forming chemical bonds, atoms are trying to attain the configuration of a Noble gas
121.
If a bonding pair of electrons is unequally shared between two atoms, the bond is:
a polar covalent bond formed (0.5 – 2.0)
122.
The electron configuration of a fluoride ion, F-1, is:
123.
Metals are good conductors of electricity because they: contain mobile valence electrons
124.
Molecule in which one end has a partial positive charge and the other end has a partial
negative charge is called a(n)
1s2 2s22p6 (same as Ne)
dipole
True or False
125.
True
The chemical properties of an element are largely determined by the number of
valence electrons the element has.
126.
False
Fluorine and chlorine each have one valence electron.
127.
False
Non-metals acquire the stable electron structure of a noble gas by losing
electrons.
128.
True
An alloy is a mixture of two or more elements, in which at least one is a metal.
129.
False
The crystal structure of ionic compounds such as sodium chloride is very
unstable.
130.
True
Ionic compounds conduct electricity only when in a molten/melted state.
131.
True
During the formation of ionic compounds, electrons are transferred from one
atom to another.
132.
True
Any part of a system with uniform composition and properties is called a phase.
133.
False
A pure substance can be a mixture.
134.
True
A heterogeneous mixture consists of two or more substances.
135.
True
A vapor is a gaseous substance.
136.
True
A compound can be chemically separated into its elements.
137.
False
Precise measurements are also accurate measurements.
138.
False
All zeros in a measurement are significant.
139.
True
Yesterday was a cool fall day. This is a qualitative measurement.
140.
True
One cubic centimeter is the same as one milliliter.
141.
True
The weight of an object changes with its location.
142.
False
A kilogram is the mass of 1mL of water at 4 °C.
143.
True
The density of a substance decreases at its temperature increases.
144.
True
Heat transfers from objects at high temperatures to objects at low temperatures.
145.
True
Oil floats on water, therefore, water’s density is greater than oil.
146.
False
The periodic table is an arrangement of elements according to similarities in their
properties.
147.
True
Relative atomic masses are expressed in amus.
148.
False
The atomic number of an element is the sum of the protons and electrons in an
atom of that element.
149.
False
According to Dalton’s atomic theory, atoms are composed of protons, electrons,
and neutrons.
150.
True
The charge on all protons is the same.
151.
True
A cathode ray is a beam that travels from a cathode to an anode.
152.
False
The position and velocity of an electron in an atom can be determined with great
certainty.
153.
False
The photoelectric effect will occur no matter what energy of light strikes a metal.
154.
True
The outermost s orbital of an atom contains two electrons.
On the periodic table, how are the following terms effected as you move down a group.
Explain why.
155.
Electronegativity generally
decreases as you move down a group because you are
adding more NRG levels, moving the valence electrons away from the nucleus, therefore it does
not attract electrons as strongly
156.
Atomic size generally
increases as you go down a group because the atom has more
NRG levels which makes it bigger in size
157.
Ionization NRG generally decreases as you go down a group because the atom has more
NRG levels therefore it will take less NRG to remove the electrons
On the periodic table, how are the following terms effected as you move across a period.
Explain why.
158.
Electronegativity generally
increases because protons have been added therefore the
nuclear charge is greater so it attracts more electrons (closer to noble gases)
159.
Atomic size generally
decreases because protons have been added therefore the nuclear
charge is greater which pulls in the electrons closer to the nucleus
160.
Ionization NRG generally increases because protons have been added therefore the nuclear
charge is greater so it attracts more electrons (closer to noble gases) making it difficult to remove
an electron
161.
For the elements whose outermost electron configurations are given below, tell the period and
the group to which each belongs.
a.
3s 2
2
Period
3
Group
2A
b.
5s 5p
4
Period
5
Group
6A
c.
2s 2 2p 1
Period
2
Group
3A
162.
Write the FULL electron configurations and orbital diagram/notation for each of the following
elements.
a.
He
d.
3d ___ ___ ___ ___ ___
4s ___
3p ___ ___ ___
3s ___
2p ___ ___ ___
2s ___
1s 
K
3d ___ ___ ___ ___ ___
4s _
3p   
3s 
2p   
2s 
1s 
e-config: 1s2, 2s2, 2p6, 3s2, 3p6, 4s1
c.
3d ___ ___ ___ ___ ___
4s ___
3p   _
3s 
2p   
2s 
1s 
e-config: 1s2, 2s2, 2p6, 3s2, 3p3
e-config: 1s2
b.
P
Al
3d ___ ___ ___ ___ ___
4s ___
3p  ___ ___
3s 
2p   
2s 
1s 
e-config: 1s2, 2s2, 2p6, 3s2, 3p1
e.
O
3d ___ ___ ___ ___ ___
4s ___
3p ___ ___ ___
3s ___
2p   _
2s 
1s 
e-config: 1s2, 2s2, 2p4
Answer the following:
163.
Chart the characteristics of ionic and covalent compounds.
Characteristics
Ionic
Covalent
Elements involved
Metals and non-metals
Non-metals only
Particles involved
Cations and anions
None
How?
Electrons are transferred
Electrons are shared
Phase at room temperature
Solid
Solid, liquid or gas
Conducts electricity
When melted/molten or
Not at all
dissolved in water (aqueous)
Melting point
High
Low
Structure
Crystalline Solid
Amphorous Solid
Attraction
Strong very stable
Weak not very stable
164.
Why does atomic size generally increase as you move down a group of the periodic table and
decrease as you move from left to right across a period?
increases as you go down a group because you are the atom has more NRG levels which
makes it bigger in size and decreases across a column because protons have been added
therefore the nuclear charge is greater which pulls in the electrons closer to the nucleus
165.
Define valence electrons. Electrons in the outer most or highest occupied NRG level
166.
State Dalton’s Atomic theory.
1. All elements are composed of tiny indivisible particles called atoms
2. Atoms of the same element are the same and atoms of different elements are
different.
3. Atoms of different elements can be physically mixed or chemically combined with
other in simple whole number ratios to form compounds.
4. Chemical reactions occur when atoms are separated, joined or rearranged. Atoms
of 1 element NEVER change into atoms of another element as a result of a chemical reaction.
167.
Compare and contrast metals and non-metals and metalloids give 1 element example for
each.
Characteristics
Metals
Nonmetal
Metalloid
Semiconductors
Solid (except Hg –
Phases
Solid, liquid or gas
Solid, liquid or gas
liquid)
Malleable
Yes very
Not at all
In between
Ductile
Yes
Not at all
In between
Conduct heat &
Yes
No
In between
Electrons
Lose
Gain
Both
Strength
Strong
Brittle
In between
Luster
Yes
No
Some do
electricity
168.
A cube of gold-colored metal with a volume of 64 cm3 has a mass of 980 g. The density of
pure gold is 19.3 g/cm3. Is this metal pure gold?
D = m = 980 g
V
= 15.3125 or 15 g/cm3
64 cm3
No, density does not match
169.
When a glass blower shapes molten glass into an ornament, does a chemical reaction occur?
Explain. No, it is a physical change because it is still glass, it now has a different shape
170.
Find the density of a rock, if its mass is 25 g and if displaces 30 mL of water.
D = m = 25 g
V
= .83333333333 g/mL
30 mL
0.83 g/mL
171.
Distinguish between physical changes and chemical changes and give two examples of each.
Example 1
Example 2
Tearing paper Melting Ice
Physical change – Alters a substance without
changing its chemical composition
Chemical change – When a completely new substance Rusting iron
is made – the chemical composition of a substance is
totally changed
172.
Burning paper
List all things that are often indications of a chemical change or reaction.
1. Change in color
2. Emission of a light
3. Formation of a gas
4. Change in Heat
5. Production of a precipitate
173.
Describe how you would separate a mixture of salt, water, and sand.
First you would remove the sand using filter and a funnel, then you could distill the water off
leaving the salt and still retaining the water or you could evaporate the water, if it was not needed.
174.
What are the electronegativity differences between non-polar covalent, polar covalent, and
ionic bonds?
175.
Nonpolar covalent = 0 – 0.4, Polar covalent = 0.5 – 2.0 and Ionic is 2.1 or greater
Find the electronegativity difference and label the bond type for the following:
a. NaCl
c. HF
e. H2O
b. O2
d. SiO2
f. MgCl2
176.
Make a chart to describe the physical properties of solids, liquids and gases.
Shape
Solid
Liquid
Gas
177.
Volume
Definite
shape
Definite
volume
Takes the
shape of the
container
Takes the
shape of the
container
Definite
volume
Takes the
volume of
the
container
Expansion
when
heated?
Very slight
Compressibility? Energy Level
None
Low NRG
level
Very slight
None
Medium
NRG level
Great
Great
High NRG
level
What is the difference between a single covalent, double covalent and triple covalent bond?
Single covalent bond – sharing of 2 electrons between atoms
Double covalent bond – sharing of 4 electrons between atoms
Triple covalent bond – sharing of 6 electrons between atoms
Name or write formula of the following compounds
178.
Fe2O3
Iron (III) oxide
179.
NH4Cl
Ammonium chloride
180.
CoBr2
Cobalt (II) bromide
181.
Calcium chloride
CaCl2
182.
Sodium iodide
NaI
183.
Aluminum nitrate
Al(NO3)3
184.
Iron (II) oxide
FeO
185.
Lead (IV) oxide
PbO2
186.
Mg3(PO4)2
Magnesium Phosphate
187.
Ag2S
Silver Sulfide
188.
N2O4
Dinitrogen tetroxide
189.
CS2
Carbon disulfide
190.
P2O5
Diphosphorus pentoxide
191.
Phosphorus trichloride
PCl3
192.
Sulfur dioxide
SO2
193.
Carbon dioxide
CO2
194.
Dihydrogen monoxide
H2O
195.
NaI
Sodium iodide
196.
List the prefixes used in naming covalent compounds.
1 = mono2 = di3 = tri4 = tetra5 = penta6 = hexa7 = hepta8 = octa9 = nona10 = deca-