Chem Test Ch. 4-6

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Isotopes have ____.
A. the same number of neutrons but different number of protons
B. the same number of protons and same number of neutrons
C. the same number of protons but different number of neutrons
D. different number protons and neutrons

C. the same number of protons but different number of neutrons

The relationships between 16O, 17O, and 18O is ___.
A. isotopes
B. isomers
C. isobars
D. they are not isotopes

A. isotopes

The relationship between 40Ar, 40K, and 40CA is ___.
A. isomers
B. isobars
C. isotopes
D. they are not isotopes

D. they are not isotopes

The process in which a nucleus spontaneously breaks down by emitting radiation is know as
A. fusion
B. transformation
C. a chain reaction
D. radioactive decay
E. translation

D. radioactive decay

Plutonium and americium are
A. radioactive transuranium elements
B. synthetic transuranium elements
B. synthetic elements
C. actinides
D. inner transition elements
E. all of the choices are correct

E. all of the choices are correct

Whichof the following has amass number of 1? Which of the following has an atomic number of 0? Which of the following is a nucleon?
A. Mass # of 1: positron
Atomic # of 0: electron
Nucleon: electron and positron
B. Mass # of 1: neutron and proton
Atomic # of 0: neutron
Nucleon: proton and neutron

B. Mass # of 1: neutron and proton
Atomic # of 0: neutron
Nucleon: proton and neutron

Which of the following does not carry proton(s)?
A. alpha rays
B. deuterium
C. gamma-rays
D. 1H

C. gamma-rays

Mass defect is ____.
A. the amount of energy absorbed when an atom forms from its subatomic particles
B. the amount of mass produced during a nuclear reaction
C. the amount of mass that is converted to energy during anuclear reaction
D. the amount of energy released when an atom forms from its subatomic particles

C. the amount of mass that is converted to energy during anuclear reaction

Banding Energy is ____.
A. the amount of energy absorbed when an atom forms from its subatomic particles
B. the amount of mass that is converted to energy during a nuclear reaction
C. the amount of mass produced during a nuclear reaction
D. the amount of energy released when an atom forms from its subatomic particles

D. the amount of energy released when an atom forms from its subatomic particles

Which of the following is not true?
A. Many radioactive nuclei release energy in the form of electromagnetic radiation, such as gamma rays.
B. Isotopes with the lowest possible n/p ratio are the most stable
C. 12C is the most stable carbon isotope.
D. A chemical reaciton involves much higher energies than a nuclear reaction.
E. 35Cl and 37Cl are isotopes.

D. A chemical reaciton involves much higher energies than a nuclear reaction

The n/p ratio of stable isotopes becomes larger than 1, when the atomic number is larger than ____.
A. 20
B. 18
C. 10
D. 24

A. 20

The only element whose most stable isotope has n/p<1 is _____.
A. helium
B. osygen
C. hydrogen
D. carbon

C. hydrogen

What is the location of each isotope on the BAnd of Stability? carbon-12 and calcium-40.
A. above-meaning they are unstable
B. directly on-meaning they are stable
C. below-meaning they are unstable

B. directly on-meaning they are stable

What is the location of each isotope on the Band of Stability? iron-56, uranium-238, and cobalt-60
A. directly on-meaning they are stable
Below-meaning they are unstable
C. above-meaning they are unstable

C. above-meaning they are unstable

What is the location of each isotope on the BAnd of Stability? hydrogen-1
A. above-meaning they are unstable
B. directly on-meaning they are stable
C. below-meaning they are unstable

C. below-meaning they are unstable

WHich of the following is true concerning particles?
A. Beta particles are helium nuclei/ They have a -1 charge. Alpha particles are X-rays
B. Beta particles are high-energy radiation. Alpha particles are protons. They have a +2 charge. Gama rays are X-rays.
C. Beta particles are high-speed electrons. They have a -1 charge. Alpha particles are helium nuclei. They have a +2 charge. Gamma rays arehigh-energy radiation.

C. Beta particles are high-speed electrons. They have a -1 charge. Alpha particles are helium nuclei. They have a +2 charge. Gamma rays arehigh-energy radiation.

Which of the following is true?
A. An alpha particle may be presented by 4/2 He. A beta particle may be respresented by )0/-1e. A gamma particle may be represented by 0/0 Y. A positron particle may be represented by 0/+1 e.
B. An alpha particle may be represented by 4/2 He. A beta particle may be represented by 1/0n. A gamma particle may be represented by 0/-1e.

A. An alpha particle may be presented by 4/2 He. A beta particle may be respresented by )0/-1e. A gamma particle may be represented by 0/0 Y. A positron particle may be represented by 0/+1 e.

In order for a nuclear equation to be balanced, what must be true (among other factors)?
A. there must be the same number of high-speed electrons on both sides of the equation.
B. there must be the same number of positrons on both sides of the equation.
C. the sums of the mass numbers on both sides of the equation must be equal.
D. there must be the same number of alpha particles on both sides of the equation.

C. the sums of the mass numbers on both sides of the equation must be equal.

IN the final step of the uranium-235 disintegration series, the parent nuclide decays to lead-207 and a beta particle. What is the parent nuclide?
A. 206/82 Pb
B. 208/82 Pb
C. 207/81 Tl
D. 207/83 Bi

C. 207/81 Tl

The uranium-238 decay series begins with the emission of an alpha particle. If the daughter decays by beta emission, what is the resulting nuclide?
A. 227/89 Ac
B. 234/90 Th
C. 233/91 Pa
D. 234/91 Pa
E. 233/90 Th

D. 234/91 Pa

A. 227/88 Ra
B. 228/89 Ac
C. 227/89 Ac
D. 228/87 Fr
E. 228/88 Ra

B. 228/89 Ac

Which of the following is NOT a beta emitting reaction?
A. 226Ra-->222Rn
B. 131I-->131Xe
C. 231Th-->231Pa
D. 90Sr-->90Y

A. 226Ra-->222Rn

When carbon-14 is converted to nitrogen-14 ____.
A. a neutron is released
B. an alpha particle is emitted
C. an electron is released
D. an electron is captured

C. an electron is released

When a neutron is transformed into a proton what else is emitted?
A. an electron
B. a beta particle
C. an alpha particle
D. Either A or B; both of them represent the same particle.

D. Either A or B; both of them represent the same particle.

What nuclide is produced when a W-181 nucleus decays by electron capture?
A. 180/75 Re
B. 180/73 Ta
C. 180/74 W
D. 181/73 Ta
E. 181/75 Re

D. 181/73 Ta

What nuclide is produced when a Mn-52 nucleus decays by electron capture?
A. 52/24 Cr
B. 53/26 Fe
C. 53/24 Cr
D. 52/26 Fe
E. 53/25 Mn

A. 52/24 Cr

What radionuclide decays to Cs-133 by electron capture?
A. 134/55 Cs
B. 134/56 Ba
C. 133/54 Xe
D. 132/54 Xe
E. 133/56 Ba

E. 133/56 Ba

Which of the following transformations is NOT an electron capture?
A. p-->n
B. 231Th-->231Pa
201Hg-->201Au
D. 81Rb-->81Kr

B. 231Th-->231Pa

The mercury-197 to gold-197 conversion is accompanied by ___.
A. an electron release
B. an alpha emission
C. a neutron capture
D. an electron capture

D. an electron capture

The product from the positron emission of 127/55 Cs is ___.
A. 126/55 Cs
B. 127/56 Ba
C. 127/54 Xe
D. 126/54 Xe
E. 123/53 I

C. 127/54 Xe

The nuclear symbol that completes the equation is a(n)
13/7 N --> 13/6 C + ?
A. neutron
B. alpha particle
C. proton
D. beta particle
E. positron

E. positron

In the final step of the uranium-238 disintegration series, the parent nuclide decays to lead-206 and an alpha particle. What is the parent nuclide?
A. 210/84 Po
B. 210/83 Bi
C. 206/84 Po
D. 202/80 Hg
E. None of the above

A. 210/84 Po

In the final step of the thorium-232 disintegration series, the parent nuclide decays to lead-208 and an alpha particle. What is the parent nuclide?
A. 212/83 Bi
B. 208/83 Bi
C. 212/84 Po
D. 208/84 Po
E. None of the above

C. 212/84 Po

As a result of alpha decay, the isotope 226/88 Ra is transformed into __
A. 222/86 Rn
B. 224/88 Pb
C. 222/88 Ra
D. 226/90 Th
E. 226/82 Ra

A. 222/86 Rn

The product from teh alpha decay of 235/92 U is ___
A. 231/90 Th
B. 236/92 U
C. 235/93 Np
D. 239/94 Pu

A. 231/90 Th

Which of the following transformations is NOT an alpha emission?
A. 225Ac-->221Fr
B. 218Po-->214Pb
C. 241Am-->237Np
D. 14C-->14N

D. 14C-->14N

When radium-226 is converted to radon-222 ___.
A. an electron is released
B. an electron is captured
C. a nuetron is released
D. an alpha particle is emitted

D. an alpha particle is emitted

What kind of transformation is each of the following?
A.40K-->Ar Electron capture
230Th-->226Ra Alpha Emission
214Bi-->214Po Beta emission

A.40K-->Ar Electron capture
230Th-->226Ra Alpha Emission
214Bi-->214Po Beta emission

True of False?

When an unstable nucleus emits a beta particle its atomic number is increased by one unit. When an unstable nucleus emits an alpha particle its mass number is decreased by four units. When an unstable nucleus expels a positron its atomic number is decreased by one unit.

True

Identify X in the reaction below.
27/13Al + 4/2 He--> X + 1/0n

A. 31P
B. 31Si
C. 30P
D. 30S

C. 30P

Consider Chadwick's bombardment of beryllium with alpha particles:
9/4Be + 4/2He--> C + ?
What is the mass product?
A. 1/1P
B. 2/1H
C. 4/2He
D. 1/0n
E. 3/1H

D. 1/0n

When 58/26Fe is bombarded with neutrons, one product is formed. What is it?
A. 56/25 Mn
B. 58/25 Mn
C. 58/27 Co
D. 57/26 Fe
E. 59/26 Fe

E. 59/26 Fe

For the following nuclear reaction, supply the missing isotope, or elementary particle 22Na--> ___ + 1/+1e
A. 22Na
B. 22Ne
C. 21Ne
D. 24Mg

B. 22Ne

For the following nuclear reaction, supply the missing isotope, or elementary particle ___ -->226Rn + 4/2He
A. 230Po
B. 222Ra
C. 230Ra
D. 230Rn

C. 230Ra

For the following nuclear reaction, supply the missing isotope, or elementary particle 37Ar + 0/-1e--> ___
A. 36Cl
B. 36Ar
C. 37Cl
D. 37K

C. 37Cl

For the following nuclear reaction, supply the missing isotope, or elementary particle 146Sm--> __ + 142Nd
A. 0/-1e
B. 1/0n
C. 0/+1e
D. 4/2He

D. 4/2He

When aluminum-27 is bombarded with a neutron, a gamma ray is emitted. What radioactive isotope is produced?
A. silicon-28
B. magnesium-28
C. silicon-27
D. aluminum-28

D. aluminum-28

The half-life of a radioisotope is
A. the time it takes for the radioisotope to lose one-half of its neutrons
B. the time it takes for the radioisotope to become an isotope with one-half of the atomic weight of the original radioisotope.
C. the time i ttakes for the radioisotope to become an isotope with one-half the atomic number of the original radioisotope
D. the time it takes for one-half ot he sample to decay
E.one-half of the itme it takes for the radioisotope to completely decay to a nonradioactive isotope.

D. the time it takes for one-half ot he sample to decay

Given the following half-lives, which of the following isotopes is the most stalbe?
A. 56s
B. .92 min
C. .015hr
D. 72s

D. 72s

Given the following half-lives, which of the following isotopes is the least stable?
A. .001s
B. 56s
C. .92s
D. 72s

A. .001s

Which of the following is NOT true?
A. the larger the half-life value, the more stable the isotope.
B. the half-life of an isotope decreases as the initial concentration decreases
C. the half life of 14C is close to 6,000 years
C. Both A and B are false

B. the half-life of an isotope decreases as the initial concentration decreases

If you start with 1/0 g of a radioactive isotope, how many grams of the original isotope remain after two half-lifes?
A. 1/2 g
B. 1/3 g
C. 1/4 g
D. 2/3 g
E. 1/8 g

C. 1/4 g

What percentage of the radionuclides in a given sample remains after three half-lives?
A. 50%
B. 33.3%
C. 12.5%
D. 25%
E. 6.25%

C. 12.5%

What percent of radioactive isotope remains after six half-lives elapse?
A. 33.3%
B. 64%
C. 16.7%
D. 8.3%
E. 1.56%

E. 1.56%

If the half-life of a hypothetical isotope is 5 hr, the leftover amount of an original quantity of 20.0 g after 15 hr will be ___
A. 2.5 g
B. 6.67 g
C. 10 g
D. 5 g

A. 2.5 g

If 160 mg of technetium-99 is administered for medical diagnosis, how much of the nuclide remains after 24 hours? (t1/2 = 6 hours)
A. 20 mg
B. 40mg
C. 27mg
D. 10mg
E. 53mg

D. 10mg

Radiocarbon dating is considered by many to be reliable up to how many years?
A. 5000 years
B. 5 million years
C. 10,000 years
5 billion years
E. 50,000 years

E. 50,000 years

What is the principle assumption for radiocarbon dating to be reliable?
A. the number of neutrons in the atmosphere has remained constant
B. the number of protons in the atmosphere has remained constant
C. the amount of nitrogen-14 in the atmosphere has remained contant
D. the amount of carbon-14 in the atmosphere has remained constant
E. the temperature of the atmosphere has remained constant

D. the amount of carbon-14 in the atmosphere has remained constant

Which of the following techniques do many scientists use to estimate geological events that occurred billions of years ago?
A. radiocarbon dating
B. potassium-lead dating
C. uranium-lead dating or potassium-argon dating
D. none of these
E. uranium-argon dating

D. none of these

Scientists have analyzed a piece of wood from Mt. Ararat that is speculated to be a fragment of Noah's Ark. The fragment contained 81.7 % of the carbon-14 found in the trees living at the time of analysis. Using the "age" equation, what is the estimated age of the wood? (half-life of carbon-14=5715 years)
A. 1700 years
B. 5700 years
C. 10,000 years
D. 12 years
E. 50,000 years

A. 1700 years

A geologist discovers a meteorite that has a uranium-238 to lead-106 ratio of 1:1. That means the percent uranium-238 remaining is 50%. Using the 'age' equation, what is the estimated age of the meteorite? (half-life uranium-238 remaning is 50%)
A. 2.2 billion years
B. 4.5 million years
C. 4.5 billion years
D. 9 billion years
E 50,000 years

C. 4.5 billion years

How long will it take for a 5 g tritium smaple to decay down to .313 g? The half-life of tritium is 12 years. Need to find the Percent Remaining first.
A. 24 years
B. 48 years
C. 12 years
D. 96 years

B. 48 years

The half-life of chlorine-34 is 1/52 seconds. How much time will pass before a given sample of chlorine-34 decays by 60%? Remember to use the Percent REMAINING.
A. 2.01 seconds
B. 1.12 seconds

A. 2.01 seconds

Sodium-24 has ahalf-life of 15 hours. How many hour is three half-lives?
A. 15 hours
B. 30 hours
C. 60 hours
D. 45 hours
E. 7.5 hours

D. 45 hours

Krypton-79 has a half-life of 35 hours. How many half-lives have passed after 105 hours?
A. 1 half-life
B. 5 half-lives
C. 2 half-lives
D. 4 half-lives
E. 3 half-lives

E. 3 half-lives

Nuclear ___ is the breaking up of a large nucleus into smaller ones.
A. fusion
B. fission

B. fission

The minimum amount of fissionable material needed for a chain reaction to be sustained is the critical mass. If the reaction is not controlled, thisis also the minimum amount of mass necessary for an explosion during a chain reaction.
True or False?

True

True or False?
A fusion reaction is more energetic than a fission reaction. Fusion is able to give back more energy than we feed it.
In the sun, nuclei of hydrogen combine to form a larger nucleus and release a great amount of energy. The process is known as fusion.
When an atom of uranium-235 is bombarded with neutrons, it splits into smaller nuclei and produces a great amount of energy. This nuclear process is called fission.

True

The main problem nuclear reactors have when uranium-235 serves as the fuel is ___
A. the consumption of more alpha particles than the available alpha particles
B. the immense amount of energy produced
C. the production of more neutrons than the reaction consumes
D. the production of gamma rays

C. the production of more neutrons than the reaction consumes

Valid concerns of nuclear fission reacotrs include:
A. nuclear explosion
B. release of radioactive materials
C. storage of nuclear waste
D. A,B, and C
E. All of the above

E. All of the above

the main problem with nuclear fusion is that there is no known structural material that can withstand the igh temperatures needed. True or False?

True

Nuclear radiation is harmful because ____.
A. of the ionizing of biological molecules
b. of the high energy particles produced
c. of the electromagnetic radiation emitted by a nucleus during the nuclear change
D. it can cause biological damage by the weakening or breaking of bonds
E. all of the above

E. all of the above

The harmful radioactive isotope produced in a nuclear bomb blast that is similar to calcium is obtained from dairy products, and accumulated in bone is _____.
A. iodine-131
B. strontium-90
C. none of these
D. both of these

B. strontium-90

The damaging effects of radiation on the body are a result of
A. the formation of unstable ions or radicals
B. the formation of radioactive atoms in the body
C. extensive damage to nerve cells
D. transmutation reactions in the body
E. the production of radioactive sodium ions in the body

A. the formation of unstable ions or radicals

During the MRI procedure the human is placed in a magnetic field and radio waves are used to probe certain nuclei in the body. The MRI technique detects the energy absorbed by hydrogen atoms in a magnetic field. True or False?

True

An imaging technnique in which a computer monitors the degree of absorption of X-ray beams is known as
A. positron emission tomography (PET)
B. computed tomography (CT)
C. a scan
D. radioactive iodine uptake (RAIU)
E. magnetic resonance imagine (MRI)

B. computed tomography (CT)

Why is it important that radioisotopes used in diagnostic tests have short half-lives?
A. this is necessary so the radioisotopes will have high energy
B. this minimizes the harmful side effects of the radiation
C. these radioisotopes are more abundant in nature
D. these radioisotopes are less expensive
E. these radioisotopes have a greater activity so they are easier to monitor

B. this minimizes the harmful side effects of the radiation

Which of the following is the easiest to block from penetrating? Which form of radiation has the greatest penetrating power?
A. Easiest to block: alpha emissions
Greatest penetrating power: gamma rays
B. Easiest to block: gamma rays
Greatest penetrating power: high-speed electrons
C. Easiest to block: beta emissions
Greatest penetrating power: alpha particles

A. Easiest to block: alpha emissions
Greatest penetrating power: gamma rays

Which of the following types of radiation has the highest energy and therfore requires the heaviest shielding?
A. visible light
B. beta particles
C. alpha particles
D. Gamma rays (Y)
E. All of these have the same energy

D. Gamma rays (Y)

Which of the following is suitable as a minimum shielding for beta particles?
A. 1 m of water
B. gloves
C. 1 m of concrete
D. air
E. 1 cm of lead

B. gloves

Which is not a way to minimize your exposure to radiation?
A. staying a longer time
B. standing behind a thick concrete wall
c. keeping a good distance
D. wearing lead-lined gloves
E. wearing a lead apron

A. staying a longer time

If absorbed internally, alpha particle emitters are the most damaging becaues alpha particles____
A. have the largest charge
B. have the greatest energy
C. consist of pure energy
D. have the greatest mass
E. consist of high energy electrons.

D. have the greatest mass

One sympton of mild radiation sickness is
A. a lowered red blood cell count
b. a raised white cell count
C. a lowered white cell count
D. a white cell count of zero
E. a raised red blood cell count

C. a lowered white cell count

Device that measure radioactivity by detecting ions formed by electrons being knocked off of gas molecules is
A. the Roentgen accumulator
B. the tricorder
C. the scintillation counter
D. the film badge
E. the Geiger counter

E. the Geiger counter

Which of the following is indicated by each 'click' from a Geiger counter?
A. one nucleus decaying
B. one half-life
C. one minute elapsing
d. one second elapsing
E. none of the above

A. one nucleus decaying

A nuit that measures activity of a radioactive sample in terms of nuclear disintegrations per second is the
A. curie
B. roentgen
C. rad
D. x-rad
E. gray

A. curie

A unit that measures the amount of energy absorbed by tissue upon exposure to radioactivity is the
A. curie
B. roentgen
C. rad
D. erg
E. geiger

C. rad

A unit that measures biological damage tohuman tissue from radioactivity is the
A. roentgen
B. geiger
C. rad
D. rem
E. Gray

D. rem

What is teh average range of constant natural background radiation which everyone receives in a year?
A. 1000-2000 mrem
B. 5000-10000 mrem
C. 100-600 mrem
D. 1-2 mrem
E. 10-40 mrem

C. 100-600 mrem

Which of the following natural radioisotopes poses a health hazard by infiltrating homes and other closed habitats?
A. carbon-14
B. tritium
C. uranium-238
D. potassium-40
E. radon-222

E. radon-222

What artificial source is responsible for the most radiation exposure we receive? It is the major source of background ionizing radiation which is not natural, i.e. synthetic.
A. smoke detectors
B. MRI machines
C. medical X rays
D. microwaves
E. nuclear power plants

C. medical X rays

An approved method used to help preserve food is exposure to what kind of radiation? it is used on vegetables to destroy germs. Cobalt-60 emits them and is used to destroy microorganisms and parasites in food
A. alpha particles
B. neutrons
C. beta particles
D. X rays
E. gamma rays

E. gamma rays

Which isotopes match their uses?
1) Gadolinium-153 : determination of relative bone density
2) iodine-131 : used in medicine for the treatment of thyroid cancer
3) chromium-51 : used in medicine for the determination of total blood volume
4) Cobalt-60 : treatment of cancer by emitting gamma rays

A. only the even ones match
B. All match
C. only odd ones match

B. All match

Which isotopes match their uses?
1) plutonium-238 : used to power heart pacemakers
2) xenon-133 : used to diagnose respiratory problems
3) iron-59 : used to diagnose a low red blood cell count
4) technetium-99 : used to diagnose and locate brain tumors
5) iridium-192 used to treat breast cancer

A. Evens match
B. Odds match
C. All match

C. All match

Which of the following statements best describes an ionic bond?
A. the bonding type present in bound, non-metal atoms
B. the equal sharing of two electrons between adjacent atoms
C. a strong lattice of positively and negatively charged atoms held together by electrical forces
D. the bonding type present between two metal atoms

C. a strong lattice of positively and negatively charged atoms held together by electrical forces

Which of the following is considered an elemental substance?
A. I2 (Iodine)
B. H2O (water)
C. Fe (an iron nail)
D. A and C are elemental substances
E. all of the preceding are elemental substances

D. A and C are elemental substances

Which of teh following exists as a diatomic molecule?
A. oxygen
B. phosphorus
C. silicon
D. neon

A. oxygen

Which of the following substances is molecular (composed of individual molecules) in composition?
A. helium, as found in a balloon
b. carbon, as coal
C. water, as a glass of water
D. copper, as an ingot

C. water, as a glass of water

Which phrase best describes a covalent bond between two atoms?
A. an exchange of nuclei between two atoms
B. uncommon, as electrons are free to jump from one atom to another
C. a stable arrangement of charged atoms held together by electrostatic forces
D. a stable arrangement of atoms made by sharing two electrons between adjacent atoms

D. a stable arrangement of atoms made by sharing two electrons between adjacent atoms

Which of teh following statements are true?
1) Covalent bonds are formed between atoms that share pairs of electrons
2) Energy is released as two atoms, such as two hydrogen atoms, form a bond
3) When covalent bonds are broken energy is released
4) Water, H2O and hydrogen peroxide, H2O2, have identical properties

A. 1,3,4
B. 1,2
C. 1,2,3,4
D. 1,2,3
E. 3,4

B. 1,2

Match the element with the correct number of valence electrons
A. Si...1, I...1, S...6, Al...3, Ne...2, N...5, He...8
B. Si...4, I...1, S...2, Al...3, Ne...8, N...5, He...1
C. Si...4, I...7, S...6, Al...3, Ne...8, N...5, He...2

C. Si...4, I...7, S...6, Al...3, Ne...8, N...5, He...2

Which of the following have the same number of outer shell electrons?
1) Oxygen and chlorine
2) Calcium and barium
3) elements in Group 15
4) Elements in Period 4

A. 2,3
B. 1,2,3,4
C. 3,4
D. 1,2,3
E. 1,2

A. 2,3

True or False?
1) In its ground state, sulfur has two valence electrons and always needs six more to reach the octet.
2) in its ground state, carbon has four valence electrons and always needs four more to reach the octet
3) The oxide anion, (O2-), has 1 unpaired electron.
4) To follow the octet rule, a neutral sulfur atom must gain 2 electrons when forming a negative ion.

2,4 are TRUE.
1,3 are FALSE

the numerical rating of an atom's ability to attract the shared electrons is called ____
A. covalency
B. redistribution
C. electronegativity
D. ionization

C. electronegativity

Which of teh following is the most electronegative element on the periodic table?
A. fluroine
B. sodium
c. oxygen
D. carbon

A. fluorine

Which of the following is the lease electronegative?
A. chlorine
B. hydrogen
c. sodium
D. sulfur

C. sodium

Consider a bond A-B. Is the following TRUE or FLASE?

If the difference in electronegativity is 1.0, the bond is considered polar covalent.
If the difference in electronegativitiy is 3.5, the bond is considered ionic
If the difference in electronegativity is 0.0, the bond is considered nonpolar covalent

TRUE

Which of the following statements is true?
1) a chemical compound formed from lithium and chlorine should be ionic in character
2) Compounds formed from carbon and hydrogen should be ionic in character
3) Metals are generally more lectronegative than non-metals
4) Metals are always going to be the more electropositive elements in a bond as long as they are attached to a non-metal
5) the electrons in a carbon-chlorine covalent bond are 'shared' exactly equally between these two atoms

1,4 are TRUE
2,3,5 are FALSE

Which of the bonds would you expect to be ionic?
A. C-S
B. Na-F
C. F-F
D. N-O

B. Na-F

Which of the following covalent bonds would you expect to be the most polar?
A. C-Cl
B. C-C
C. C-F
D. C-H

C. C-F

Which of the following phrases best describes the H-O bonds present in water (H2O)?
A. nonpolar and ionic
B. polar and covalent
C. polar and ionic
D. nonpolar and covalent

B. polar and covalent

If the electrons are shared equally between the two atoms, the bond is called ____. when the valence electrons between atoms are transferred the bond is called ____. When electrons in a bond are shared unequally the bond is ___.
A. polar covalent, non-polar covalent, ionic
B. non-polar covalent, ionic, polar covalent
C. ionic, polar covalent, non-polar covalent
D. non-polar covalent, polar covalent, ionic

B. non-polar covalent, ionic, polar covalent

When a compound is composed of a metal and non-metal it is called _____.
A. ionic
B. covalent
C. coordinate
D. either B or C

A. ionic

Which of the following compounds has a covalent bond?
A. NaCl
B. KBr
C. LiH
D. H2

D. H2

How many valence electrons are needed to construck the Lewis dot structure of the BCl3 molecule?
A. 21
b. 11
C. 24
D. 32

C. 24

The nitrogen molecule, N2, has 10 total valence electrons. True or False?

True

Nitrogen trifluoride, NF3, has ___ valence electrons. Carbon tetrafluroide, CF4, has ___ total valence electrons.
A. 24, 32
B. 26, 24
C. 24, 24
D. 26, 32

D. 26, 32

How many valence electrons are required when constructing a complete Lewis dot structure of the compound CF2Cl2?
A. 66
B. 58
C. 32
D. 29

C. 32

the number of valence electrons in the carbonate anion, CO3 2-, is ___. The number of valence electrons in the nitrate anion, NO3 1-, is __. the phosphaet anion, PO4 3-, has __ valence electrons.
A. 20, 22, 26
B. 24, 22, 32
C. 24, 24, 32
D. 24, 24, 26

C. 24, 24, 32

The number of valence electrons in the ammonium ion, NH4 1+, is 10. True or False?

False

True or False? A single bond is always represented by two electrons?
Multiple covalent bonds arise when two atoms will share more than one pair of electrons with each other.

True

The central atom in sulfuric acid is ___.
A. sulfur
B. oxygen
C. hydrogen
D. none of the above

A. Sulfur

Water has __ covalent bonds and __ lone pairs.
A. 2, 0
B. 2, 2
C. 2, 6
D. 2, 4

B. 2, 2

Nitrogen trifluoride, NF3, has ___ bonds, __ of which are single bonds. It also has ___ lone pairs or electrons.
A. 8, 3, 10
B. 3, 3, 10
C. 5, 1, 9
D. 7, 2, 9

B. 3, 3, 10

The nitrogen in ammonia, NH3, and the phosphorus in phosphine, PH3, both have ___ bonds and ___ non-bonded pair of electrons.
A. 3, 0
B. 4, 0
C. 3, 1
D. 4, 1

C. 3, 1

Methane, CH4, has ___ covalent bonds and ___ lone pairs.
A. 4, 1
B. 2, 4
C. 4, 0
D. 4, 2

C. 4, 0

Hydrazine, N2H4, has _ covalent bonds and __ lone pairs.
A. 4, 2
B. 2, 2
C. 3, 4
D. 5, 2

D. 5, 2

True or False?
Silicon in silicon dioxide, SiO2, has four bonds(two double bonds) and zero non-bonded pair of electrons.
Carbon dioxide, CO2, obeys the octet rule
There are no lone pairs in ethane, C2H6

True

What are the number of single bonds in C2H6O?
A. 7
B. 8
C. 5
D. 6

B. 8

Which of teh following has more than one double bond?
A. chlorine gas
b. carbon monoxide
C. oxygen gas
D. nitrogen gas
E. carbon dioxide

E. carbon dioxide

Which of the following gases does NOT have a triple bond?
a. hydrogen cyanide, HCN
B. carbon dioxide
C. acetylene, C2H2
D. nitrogen gas

B. carbon dioxide

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