The strongest interactions between molecules of ammonia ( NH3) are

A) dipole-dipole.

B) dispersion forces.

C) hydrogen bonds.

D) ionic bonds.

E) polar covalent. 

Significant figures are important because they indicate

A) the number of measurements.

B) the accuracy of a measurement.

C) the accuracy of the conversion factor.

D) the precision of a measurement.

E) the number of digits on a calculator.

The name of the Cu+ ion is

A) copper(II).

B) cuprum.

C) cobalt.

D) copper.

E) copper(I). 

Which of the following types of radiation has the highest energy?

A) beta-particles

B) alpha-particles

C) gamma-rays

D) visible light

E) All of these have the same energy. 

In ionic compounds, ________ lose their valence electrons to form positively charged ________.

A) nonmetals; cations

B) metals; polyatomic ions

C) nonmetals; anions

D) metals; anions

E) metals; cations

The number of electron levels in a magnesium atom is

A) 1.

B) 2.

C) 3.

D) 4.

E) 5

The shape of the carbon tetrachloride molecule is

A) pyramidal.

B) tetrahedral.

C) linear.

D) octagonal.

E) square.

 In a molecule with covalent bonding

A) atoms are held together by sharing electrons.

B) oppositely charged ions are held together by strong electrical attractions.

C) atoms of metals form bonds to atoms of nonmetals.

D) atoms of noble gases are held together by attractions between oppositely charged ions.

E) atoms of different metals form bonds. 

9) What is missing in the nuclear reaction shown below? 10 5 B + 4 2 He  ________ + 1 0 n

A) a neutron

B) 13 5 N

C) 13 7 B

D) 13 7 N

E) 14 7 N

What is required for a nuclear transmutation to occur?

A) very high temperature

B) a corrosive environment

C) gamma emission

D) a particle to collide with a nucleus

E) spontaneous nuclear decay

There are more students skipping an afternoon class because afternoon naps are important. Considering the concepts of the Scientific Method this would be a(n)

A) hypothesis.

B) theory.

C) experiment.

D) observation.

E) all the above

A) hypothesis.

Which of the following is not a base SI unit?

 A) meters

B) seconds

C) inches

D) kilograms

E) mo

At this time, elements with an atomic number greater than __________ have not been found in nature.

A) 266

B) 78

C) 87

D) 92

E) 275

The VSEPR theory allows us to determine the most favorable

A) color of a compound.

B) charge on an ion.

C) formula for a compound.

D) shape of a molecule.

E) bond type for a molecule.

A sample of cerium -141 for a diagnostic test was dissolved in saline solution to an activity of 4.5 mCi/mL. If the patient undergoing the test needs a dose of 10. mCi, how much of the solution should be injected into the patient?

A) .45 mL

B) 45 mL

C) 22 mL

D) 2.2 mL

E) 4.5 mL 

Which one of the following, by definition, cannot be a pure substance?

A) sugar crystals

B) pure water droplets

C) carbon powder

D) solid gold

E) kool aid 

What is the formula of the nitride ion?

A) NO3 3-

B) N3-

C) NO2 -

D) NO3 -

E) NO3 2

The electron dot symbol below could represent which of the following elements?

A) Al

B) O

C) Ne

D) Na

E) C

When an alpha particle is emitted from the nucleus of an atom, the nuclear mass

 A) decreases by two units.

B) increases by one unit.

C) decreases by four units.

D) increases by two units.

E) remains the same. 

In an electron-dot structure of an element, the dots are used to represent

A) only the electrons that will participate in bond formation.

B) the electrons that the element will gain when it forms a compound.

C) all of the electrons in the atom.

D) the valence electrons.

E) the electron arrangement.

An anion always

A) has a positive charge.

B) has a negative charge.

C) contains a metal and a nonmetal.

D) forms covalent bonds.

E) contains a group of two or more atoms with a positive charge. 

What is the abbreviated electron configuration for nickel (atomic number 28)?

A) [Ar]4s 24p 4

B) [Kr]4s 23d 8

C) [Ar]3d 8

D) [He]2s 22p 3

E) [Ar]4s 23d 8

The octet rule indicates that

A) all of the shells in an atom hold a maximum of 8 electrons.

B) the noble gases react with other compounds to get 8 valence electrons.

C) all of the noble gases have eight total electrons.

D) atoms lose, gain, or share valence electrons to have 8 valence electrons.

E) all of the Group A elements have 8 valence electrons. 

Which of the following elements has the lowest electronegativity?

A) O

B) Li

C) N

D) C

E) F

 The p sublevel can hold a total of how many electrons?

A) 2

B) 6

C) 10

D) 3

E) 4

How many valence electrons are in the electron-dot structure of H2O?

A) 6

B) 4

C) 8

D) 2

E) 10

According to the Bohr atomic model, the third energy level in an atom can hold how many electrons?

A) 9

B) 6

C) 18

D) 2

E) 8

Which one of the following is most likely to lose electrons when forming an ion?

A) S

B) F

C) P

D) N

E) Rh

A group of covalently bonded atoms that has an overall electrical charge is called a(n)

A) ionic compound.

B) molecule.

C) cation.

D) anion.

E) polyatomic ion. 

 Which of the following polyatomic ions has a positive charge?

A) nitrate

B) hydrogen carbonate

C) sulfate

D) ammonium

E) hydroxide

Ionic bonding is expected in which of these compounds?

A) OF2

B) KF

C) HF

D) Cl2

E) H2

What is the element with the electron configuration 1s 22s 22p 63s 23p 5?

A) F

B) Ar

C) S

D) Cl

E) Be

Of the elements: B, C, F, Li, and Na, the element with the smallest atomic radius is

A) B.

B) C.

C) F.

D) Li. 

E) Na

According to the Bohr atomic theory, electrons in an atom travel in __________ around the nucleus.

A) shells

B) steps

C) shifts

D) orbits

E) jumps

Of the elements: B, C, F, Li, and Na. The element with the smallest ionization energy is

 A) B.

B) C.

C) F.

D) Li.

E) Na. 

The most widely used medical isotope in nuclear medicine is

A) I-125.

B) Co-60.

C) P-32.

D) I-131.

E) Tc-99m. 

The symbol 0 +1 e is a symbol used for a(n)

A) gamma ray.

B) positron.

C) alpha particle.

D) proton.

E) beta particle.

Which of the following substances contains a nonpolar covalent bond?

A) N2

B) NH3

C) H2O

D) NaCl

E) MgF2

The correct name for the compound N2O3 is

A) dinitride trioxide.

B) dinitrogen oxide.

C) dinitrogen trioxide.

D) nitrogen oxide.

E) nitrogen trioxide.

An ionic compound

A) contains only cations.

B) has a net charge of zero.

C) has a net positive charge.

D) contains only anions.

E) has a net negative charge

Sodium-24 has a half-life of 15 hours. How many hours is three half-lives?

A) 45 hours

B) 15 hours

C) 60 hours

D) 30 hours

E) 7.5 hours

The number of electrons in the outer energy level of a neutral atom of boron (atomic number 5) is

A) 2.

B) 8.

C) 5.

D) 10.

E) 3. 

Which one of the following compounds contains an ion with a 3+ charge?

A) MgCl2

B) FeCl3

C) CuCl

D) KCl

E) Na2O

The Pauli Exclusion Principle tells us that

A) more than two protons are excluded from the same atomic orbital.

B) different energy electrons are excluded from the same orbital.

C) two electrons in the same orbital must be of opposite spin.

D) more than two electrons are excluded from the nucleus.

E) electrons in the same sublevels cannot be in the same subshells. 

The nuclear reaction 126 50 Sn  126 51 Sb + ?

is an example of

A) translation.

B) fusion.

C) beta decay.

D) alpha decay.

E) fission.

Which of the following is suitable as a minimum shielding for beta particles?

A) gloves

B) air

C) 1 cm of lead

D) 1 m of water

E) 1 m of concrete

The correct name for the C2H3O2 - ion is

A) dicarbotrihydroxate.

B) ethanate.

C) acidate.

D) acetate.

E) oxalate

Of the elements: B, C, F, Li, and Na. The element with the most metallic character is

A) B.

B) C.

C) F.

D) Li.

E) Na