BIO 181 NAU- Exam 1 | 160 Questions and
Correct Answers (verified answers) | New
2026/27 Update
Matter - ANSWERS Anything that occupies space and has a mass
Three Physical States of Matter - ANSWERS Solid, liquid, gas
Element - ANSWERS Substance that cannot be broken down into other
substances by chemical reactions
Four elements that make up about 96% of the weight and most cells: -
ANSWERS Oxygen, carbon, hydrogen, nitrogen
Atoms - ANSWERS The smallest functional units of matter that form ALL
chemical substances
Three subatomic particles - ANSWERS Protons, Neutrons, Electrons
Protons - ANSWERS Positive charge, found in nucleus. Number of protons is
what distinguishes one element from another
Atomic number - ANSWERS How many protons are in an element
,Mass number - ANSWERS sum of the number of protons and neutrons in its
nucleus
Isotopes - ANSWERS Forms of an element with different numbers of neutrons
than protons. Ex; Carbon 12 = 6 protons and 7 neutrons.
Gaining vs. Losing electrons - ANSWERS N+1 = Losing electron
N-1 = Gaining electron
Electrons = electronegative
Octet rule - ANSWERS Atoms are most stable when their outer shell is full. The
outer shell has to be filled with 8 electrons EXCEPT Hydrogen and Helium with just
2 electrons.
Valence Electrons - ANSWERS Electrons more likely to form bonds, taken away,
or shared with other atoms. Electrons in the outer shell
Compounds - ANSWERS Putting two elements together
Two types of chemical bonds - ANSWERS Ionic and covalent
Ionic Bonds - ANSWERS ELECTRON SWAP- formed between oppositely charged
ions. Ex; NaCl
Ions (2 types) - ANSWERS Charged atoms
Cations: Have a net positive charge (+)
, Anions: Have a net negative charge (-)
Ionic - ANSWERS Something with a charge
Covalent Bond - ANSWERS Forms when two atoms SHARE one or more pairs
of outer-shell electrons. These bonds are the strongest of bonds.
Polar Molecules - ANSWERS An uneven distribution of charge Ex; H2O.
Hydrogen are slightly positive, oxygen is slightly negative.
Hydrogen Bond - ANSWERS A weak attraction between a partially positive
hydrogen and a partially negative atom like Oxygen. Causes cohesion
Cohesion - ANSWERS The tendency of molecules of the same kind to stick
together. Ex; sipping through a straw. In order for the water to be sucked up and
stuck together is cohesion
Heat - ANSWERS The amount of energy associated wit hteh movement of the
atoms and molecules in a body of matter
Temperature - ANSWERS Measures the intensity of heat
Evaporative Cooling - ANSWERS Occurs when a substance evaporates and the
surface of the liquid remaining behind cools down. Ex; sweating
Aqueous Solution - ANSWERS When water is the solvent
Correct Answers (verified answers) | New
2026/27 Update
Matter - ANSWERS Anything that occupies space and has a mass
Three Physical States of Matter - ANSWERS Solid, liquid, gas
Element - ANSWERS Substance that cannot be broken down into other
substances by chemical reactions
Four elements that make up about 96% of the weight and most cells: -
ANSWERS Oxygen, carbon, hydrogen, nitrogen
Atoms - ANSWERS The smallest functional units of matter that form ALL
chemical substances
Three subatomic particles - ANSWERS Protons, Neutrons, Electrons
Protons - ANSWERS Positive charge, found in nucleus. Number of protons is
what distinguishes one element from another
Atomic number - ANSWERS How many protons are in an element
,Mass number - ANSWERS sum of the number of protons and neutrons in its
nucleus
Isotopes - ANSWERS Forms of an element with different numbers of neutrons
than protons. Ex; Carbon 12 = 6 protons and 7 neutrons.
Gaining vs. Losing electrons - ANSWERS N+1 = Losing electron
N-1 = Gaining electron
Electrons = electronegative
Octet rule - ANSWERS Atoms are most stable when their outer shell is full. The
outer shell has to be filled with 8 electrons EXCEPT Hydrogen and Helium with just
2 electrons.
Valence Electrons - ANSWERS Electrons more likely to form bonds, taken away,
or shared with other atoms. Electrons in the outer shell
Compounds - ANSWERS Putting two elements together
Two types of chemical bonds - ANSWERS Ionic and covalent
Ionic Bonds - ANSWERS ELECTRON SWAP- formed between oppositely charged
ions. Ex; NaCl
Ions (2 types) - ANSWERS Charged atoms
Cations: Have a net positive charge (+)
, Anions: Have a net negative charge (-)
Ionic - ANSWERS Something with a charge
Covalent Bond - ANSWERS Forms when two atoms SHARE one or more pairs
of outer-shell electrons. These bonds are the strongest of bonds.
Polar Molecules - ANSWERS An uneven distribution of charge Ex; H2O.
Hydrogen are slightly positive, oxygen is slightly negative.
Hydrogen Bond - ANSWERS A weak attraction between a partially positive
hydrogen and a partially negative atom like Oxygen. Causes cohesion
Cohesion - ANSWERS The tendency of molecules of the same kind to stick
together. Ex; sipping through a straw. In order for the water to be sucked up and
stuck together is cohesion
Heat - ANSWERS The amount of energy associated wit hteh movement of the
atoms and molecules in a body of matter
Temperature - ANSWERS Measures the intensity of heat
Evaporative Cooling - ANSWERS Occurs when a substance evaporates and the
surface of the liquid remaining behind cools down. Ex; sweating
Aqueous Solution - ANSWERS When water is the solvent
