Answers(2) D (12) C (22) D (32) C(3) A (13) B (23) A (33) A(4) B (14) C (24) C (34) B(5) D (15) B (25) B(6) C (16) D (26) D(7) C (17) B (27) A(8) A (18) C (28) A(9) A (19) C (29) C(10) D (20) C (30) B(11) B (21) B (31) D

The modern model of the atom is based on the work ofA.) one scientist over a short period of timeB.) one scientist over a long period of time

C.) many scientists over a short period of timeD.) many scientists over a long period of time

In Rutherford's gold foil experiments, some alpha particles were deflected from their original paths but most passed through the foil with no deflection. Which statement about gold atoms is supported by these experimental observations?

A.) Gold atoms consist mostly of empty space

B.) Gold atoms are similar to alpha particlesC.) Alpha particles and gold nuclei have opposite chargesD.) Alpha particles are more dense than gold atoms

The region labeled "X" in the diagram has a charge that is:

A.) positiveB.) negativeC.) neutral

The nucleus of most atoms is made up of:

A.) protons and electronsB.) electrons and protonsC.) neutrons and electronsD.) protons and neutrons

The _______________ constitute(s) most of the volume of an atom.

A.) nucleusB.) protonsC.) electron cloudD.) neutrons

The charge and mass number of a proton are:

A.) charge = 0, Mass number = 1B.) charge = -1, Mass number = 0C.) charge = +1, Mass number = 1D.) charge = +1, Mass number = 0

The charge and mass number of an electron are:

A.) charge = -1, Mass number = 0B.) charge = +1, Mass number = 0C.) charge = 0, Mass number = 1D.) charge = +1, Mass number = 1

The region labeled "Y" in the diagram has a charge that is:

A.) positiveB.) negativeC.) neutral

Most of the mass of the atom can be found in the:

A.) chargesB.) electron cloudC.) electronsD.) nucleus

In which pair do the particles have approximately the same mass?

A.) proton and electronB.) proton and neutronC.) neutron and electronD.) neutron and beta particle

Which statement is true about the charges assigned to an electron and a proton?A.) Both an electron and a proton are positiveB.) An electron is positive and a proton is negativeC.) An electron is negative and a proton is positiveD.) Both an electron and a proton are negative

The charge and mass number of a neutron are:

A.) charge = +1, Mass number = 0B.) charge = 0, Mass number = 1C.) charge = +1, Mass number = 1D.) charge = -1, Mass number = 0

What is the total charge of the nucleus of a nitrogen atom?

A.) -7B.) 0C.) +7D.) +14

What is the atomic number of an element that has six protons and eight neutrons?

A.) 2B.) 6C.) 8D.) 14

Compared to a proton, an electron hasA.) a greater quantity of charge and the same signB.) a greater quantity of charge and the opposite signC.) the same quantity of charge and the same signD.) the same quantity of charge and the opposite sign

What is the total number of electrons in an atom of potassium?

A.) 18B.) 19C.) 20D.) 29

What is the total number of electrons found in an atom of sulfur?

A.) 6B.) 8C.) 16D.) 32

Which two particles make up most of the mass of an atom?

A.) electron and neutronB.) electron and protonC.) proton and neutronD.) proton and positron

What is the mass number of an atom which contains 28 protons, 28 electrons, and 34 neutrons?

A.) 28B.) 56C.) 62D.) 90

What is the total number of neutrons in an atom of an element that has a mass number of 19 and an atomic number of 9?

A.) 9B.) 10C.) 19D.) 28

The mass number of an atom is determined by:

A.) adding the neutrons and electronsB.) adding the protons and electronsC.) the number of protons onlyD.) adding the neutrons and protons

The nucleus of an atom of cobalt-58 contains

A.) 27 protons and 31 neutronsB.) 27 protons and 32 neutronsC.) 59 protons and 60 neutronsD.) 60 protons and 60 neutrons

The nucleus of which atom contains 48 neutrons?

Atoms of different isotopes of the same element differ in their total number of

A.) protonsB.) neutronsC.) electrons

Isotopes (such as hydrogen-1, hydrogen-2, and hydrogen-3) are atoms of the same element that differ in:

A.) the number of electronsB.) the atomic numberC.) the number of protons in the nucleusD.) the number of neutrons in the nucleus

Which atom contains exactly 15 protons?

A.) phosphorus-32B.) sulfur-32C.) oxygen-15D.) nitrogen-15

Which atoms are isotopes of the same element?

The atomic mass of an element is calculated using theA.) atomic number and the ratios of its naturally occurring isotopesB.) atomic number and the half-lives of each of its isotopesC.) masses and the ratios of its naturally occurring isotopesD.) masses and the half-lives of each of its isotopes

Atoms of an unknown element have the following masses and percent abundance: 90.92% of the atoms have amass of 19.988 amu, 0.26% of the atoms have a mass of 20.983 amu and 8.82% of atoms have a mass of 21.978 amu.Calculate the average atomic mass of this element.A.) 20.983 amuB.) 20.166 amuC.) 25.567 amuD.) 19.988 amu

The atomic number of an element is always equal to:A.) the number of protons plus the number of neutronsB.) the number of protons plus the number of electronsC.) the number of neutrons in the atom

D.) the number of protons in the atomE.) the number of electrons in the atom

When you change the number of electrons in an atom, you produce a different

A.) isotopeB.) type of atomC.) ionD.) mass number

How many electrons are contained in an Au+3 ion?

A.) 76B.) 79C.) 82D.) 197

An ion with 5 protons, 6 neutrons, and a charge of +3 has an atomic number of

A.) 2B.) 5C.) 6D.) 8E.) 11