Biology - Chapter 2
An atom has 8 protons, 9 neutrons, and 8 electrons. This atom has an atomic number of ______, an atomic mass of ______, and an overall charge of ______.
8; 17; 0
Which of the following are subatomic particles? A. Electrons B. Ions C. Protons D. Neutrons E. Orbitals
A. Electrons C. Protons D. Neutrons
By determining the ratio of the different _________ of carbon and other elements in a sample, scientists are able to accurately determine the age of the sample.
Isotopes
An electrically neutral atom has an atomic number of 11 and an atomic mass of 23. This atom has _______ protons, _______ neutrons, and ________ electrons.
11, 12, 11
An electrically neutral atom has an atomic number of 6 and an atomic mass of 14. This atom has __________ protons, ___________ neutrons, and ___________ electrons.
6, 8, 6
What can be accurately estimated by determining the ratio of the different isotopes of carbon in a sample? A. Weight B. Age C. Size D. Mass
B. Age
A sodium atom that has lost an electron and has an overall positive charge is an example of which of the following? A. Anion B. Cation C. Isotope D. Isomer
B. Cation
How does the decay rate of different radioactive isotopes compare? A. All radioactive isotopes decay at the same rate. B. Different radioactive isotopes decay at different rates. C. Most radioactive isotopes decay at the same rate, with a few notable exceptions.
B. Different radioactive isotopes decay at different rates.
How does the decay rate of different radioactive isotopes compare? A. Most radioactive isotopes decay at the same rate, with a few notable exceptions. B. Different radioactive isotopes decay at different rates. C. All radioactive isotopes decay at the same rate.
B. Different radioactive isotopes decay at different rates.
Which subatomic particles are located in the nucleus of an atom? A. Electrons B. Neutrons C. Ions D. Protons
B. Neutrons D. Protons
In the simple "Bohr model" of atoms shown here, the tan spheres (identified by arrows) represent which of the following? A. electrons B. protons C. daltons D. orbitals
B. Protons
Which subatomic particles determine the atomic mass of an atom? A. Protons only B. Protons and neutrons C. Protons and electrons D. Neutrons only
B. Protons and neutrons
Which of the following defines isotopes that are unstable and tend to break apart into elements with lower atomic numbers while releasing a significant amount of energy? A. Electronegative B. Radioactive C. Molecular
B. Radioactive
A chlorine atom that has gained an electron and has an overall negative charge is an example of a(n) ______. A. isotope B. anion C. cation D. isomer
B. anion
The number and configuration of electrons determines an element's ______. A. isotopic properties B. chemical properties C. radioactivity
B. chemical properties
The atomic number of an element refers to the number of ______ in the atoms of that element. A. orbitals B. protons C. electrons D. neutrons
B. protons
Atoms of different chemical elements can be differentiated based on the number of ______. A. neutrons in the nucleus B. protons in the nucleus C. orbitals in the outermost shell D. electrons in the outermost shell E. electrons in all shells
B. protons in the nucleus
Within an atom, ______ and ______ have nearly equal masses, while ______ have a much smaller mass. A. neutrons; electrons; protons B. protons; neutrons; electrons C. protons; electrons; neutrons
B. protons; neutrons; electrons
For any given isotope, such as C^14, the rate of decay can be described as which of the following? A. Depends on how old the sample is B. Depends on temperature C. Constant D. Variable
C. Constant
Atomic mass is measured in which of the following units? A. Grams (g) B. Pounds (lbs) C. Daltons (Da)
C. Daltons (Da)
Within an atom, where are electrons found? A. Concentrated at one end of the atom with the nucleus at the opposite end B. Evenly distributed throughout the atom C. In orbitals that surround the nucleus D. In orbitals located inside the nucleus E. In the nucleus
C. In orbitals that surround the nucleus
During radioactive decay, an atom typically breaks up into elements with which of the following? A. Higher atomic numbers B. The same atomic numbers C. Lower atomic numbers
C. Lower atomic numbers
A dalton is a unit of which of the following? A. Charge B. Weight C. Mass D. Electronegativity E. Size
C. Mass
Isotopes are atoms of the same element that differ in the number of which of the following? A. Electrons B. Protons C. Neutrons D. Orbitals
C. Neutrons
Which of the following defines isotopes that are unstable and tend to break apart into elements with lower atomic numbers while releasing a significant amount of energy? A. Electronegative B. Molecular C. Radioactive
C. Radioactive
When a larger atom breaks apart into smaller atoms, along with the release of a significant amount of energy, this is referred to as which of the following? A. Ionic decay B. Ionization C. Radioactive decay D. Dissociation
C. Radioactive decay
In a neutral atom, the number of electrons is equal to which of the following? A. The atomic number minus the atomic mass B. The atomic mass C. The atomic number D. The atomic mass minus the atomic number
C. The atomic number
If two atoms belong to the same element, which of the following must be true? A. They must have the same number of electrons. B. They must have the same number of neutrons. C. They must have the same number of protons.
C. They must have the same number of protons.
Carbon-12, carbon-13, and carbon-14 are ______. A. different elements of the same isotope B. different molecules which contain different amounts of C C. different isotopes of the same element
C. different isotopes of the same element
An atom has 11 protons, 12 neutrons, and 10 electrons. This atom has an atomic number of ______, an atomic mass of ______, and an overall charge of ______. A. 11; 12, +1 B. 11; 23, -1 C. 23; 12, +1 D. 11; 23; +1
D. 11; 23; +1
What do we call a substance that cannot be broken down into simpler substances by ordinary chemical means? A. A mixture B. A compound C. A solution D. An element
D. An element
The volume of space around the nucleus where an electron is most likely to be found is known as which of the following? A. Electron volume B. Electron shell C. Energy level D. Electron orbital
D. Electron orbital
Isotopes are atoms of the same element that differ in the number of which of the following? A. Protons B. Orbitals C. Electrons D. Neutrons
D. Neutrons
When a larger atom breaks apart into smaller atoms, along with the release of a significant amount of energy, this is referred to as which of the following? A. Dissociation B. Ionization C. Ionic decay D. Radioactive decay
D. Radioactive decay
A neutral atom has no net electrical charge. Why? A. There are equal numbers of electrons and neutrons in the atom. B. The atomic mass and the atomic number are equal. C. There are equal numbers of protons and neutrons in the atom D. There are equal numbers of protons and electrons in the atom.
D. There are equal numbers of protons and electrons in the atom.
_______ can be defined as any substance that has mass and occupies space.
Matter
_____ isotopes, such as carbon-14, are unstable and tend to break apart into elements with lower atomic numbers while releasing a significant amount of energy.
Radioactive
_______ isotopes, such as carbon-14, are unstable and tend to break apart into elements with lower atomic numbers while releasing a significant amount of energy.
Radioactive
Atoms with a net negative charge are known as ________, whereas atoms with a net positive charge are known as _________.
anion, cation
Atoms with a net negative charge are known as _________, whereas atoms with a net positive charge are known as ________.
anions, cations
If an atom gains or loses a(n) ________, it acquires a net electrical charge and becomes an ion.
electron
An atom is composed of a central nucleus which is surrounded by which orbiting particles?
electrons
Subatomic particles called __________ can be found at various distances from the nucleus (please only write the name of the particle without specifying its charge or other properties).
electrons
Subatomic particles called ___________ can be found at various distances from the nucleus (please only write the name of the particle without specifying its charge or other properties).
electrons
The green spheres (indicated by arrows) in the simple "Bohr model" of atoms shown here represent ______.
electrons
A substance that cannot be broken down into simpler substances by ordinary chemical means is called a(n)
element
______ atoms always have one proton.
hydrogen
__________ atoms usually have no neutrons.
hydrogen
Atoms, in which the number of electrons does not equal the number of protons, are called ________
ions
By determining the ratio of the different ___________ of carbon and other elements in a sample, scientists are able to accurately determine the age of the sample.
isotopes
C^12, C^13, and C^14 are examples of different _______.
isotopes
Anything that has mass and occupies space is defined as _________
matter
Isotopes differ in the number of ______ they contain.
neutrons
Isotopes differ in the number of _______ they contain.
neutrons
Almost all the mass of an atom is located in the _________
nucleus
Generally speaking, an atom is made of a central _________ which is surrounded by orbiting __________.
nucleus, electrons
An atom's electrons are typically found in regions called __________; those regions can be found at varying distances from the nucleus.
orbitals
A cation has a net _____ charge, while an anion has a net ______ charge.
positive, negative
Among subatomic particles, a(n) ________ has a charge of +1, a(n) ________ has a charge of -1, and a(n) _________ has no charge.
proton, electron, neutron
The three main types of subatomic particles are
proton, neutron, electron
Atomic number refers to the number of _______ in an atom
protons
Atoms of the same element always have the same number of ________ in the nucleus, and this number is unique for that element.
protons
Atoms of the same element always have the same number of __________ in the nucleus, and this number is unique for that element.
protons
The atomic mass of an atom is equal to the sum of the masses of its __________ and _________
protons, neutrons
During radioactive decay, an atom typically breaks up into elements with which of the following? A. Lower atomic numbers B. Higher atomic numbers C. The same atomic numbers
A. Lower atomic numbers
During radioactive decay, an atom typically breaks up into elements with which of the following? A. Lower atomic numbers B. The same atomic numbers C. Higher atomic numbers
A. Lower atomic numbers
Which two particles are the primary determinants of an element's atomic mass? A. Neutrons B. Electrons C. protons
A. Neutrons, C. Protons
Where is most (almost all) of the mass of an atom located? A. Nucleus B. Neutrons C. Protons D. Orbitals
A. Nucleus
The number and configuration of electrons determines an element's ______. A. chemical properties B. isotopic properties C. radioactivity
A. chemical properties
The chemical behavior of an atom is determined by the number and configuration of its ______. A. neutrons B. isotopes C. electrons D. protons
c. electrons
