LSU Biology 1201 Exam 1 Gregg
2026 Exam Questions and Verified
Answers | Already Graded A+
organisms are composed of _______________ - 🧠 ANSWER ✔✔matter
anything that takes up space and has mass - 🧠 ANSWER ✔✔matter
a substance that cannot be broken down to other substances by chemical
reactions
example: hydrogen - 🧠 ANSWER ✔✔element
a substance consisting of two or more elements in a fixed ratio
,example: water (H2O) - 🧠 ANSWER ✔✔compound
the smallest unit of matter that still retains the properties of an element - 🧠
ANSWER ✔✔atom
atoms are composed of subatomic particles. list the subatomic particles
and their charges - 🧠 ANSWER ✔✔neutron (no charge), proton (positive
charge), electron (negative charge)
neutrons and protons form the ____________ - 🧠 ANSWER ✔✔atomic
nucleus
neutron mass and proton mass are almost identical and are measured in
____________ - 🧠 ANSWER ✔✔daltons
the number of protons in an element's nucleus - 🧠 ANSWER ✔✔atomic
number
the sum of protons plus neutrons in the nucleus of an element - 🧠 ANSWER
✔✔mass number
the atom's total mass, can be approximated by the mass number - 🧠
ANSWER ✔✔atomic mass
,two atoms of an element that differ in the number of neutrons - 🧠 ANSWER
✔✔isotope
isotopes that decay spontaneously, giving off particles and energy - 🧠
ANSWER ✔✔radioactive isotopes
an electron's state of potential energy is called its _________ - 🧠 ANSWER
✔✔energy level/electron shell
1st shell max: 2 electrons
2nd shell max: 8 electrons
3rd shell max: 8 electrons
when electrons move from a lower energy level to a higher energy level,
energy is _________ - 🧠 ANSWER ✔✔absorbed
when electrons move from a higher energy level to a lower energy level,
energy is ________ - 🧠 ANSWER ✔✔lost
electrons located in the outermost, or valence shell; chemical behavior of
the atom is determined by these electrons - 🧠 ANSWER ✔✔valence
electrons
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STATEMENT. ALL RIGHTS RESERVED
3
, electrons with a full valence shell are ____________ - 🧠 ANSWER
✔✔chemically inert
atoms with __________ valence shells can share or transfer valence
electrons with certain other atoms - 🧠 ANSWER ✔✔incomplete
attractions that hold atoms close together - 🧠 ANSWER ✔✔chemical bonds
the sharing of a pair of valence electrons by 2 atoms; the shared electrons
count as a part of each atom's valence shell
example: H2 hydrogen molecule - 🧠 ANSWER ✔✔covalent bond
consists of two or more atoms held together by covalent bonds
example: water (H2O)
2 hydrogen atoms + 1oxygen atom - 🧠 ANSWER ✔✔molecule
the sharing of one pair of valence electrons - 🧠 ANSWER ✔✔single
covalent bond
the sharing of two pairs of electrons - 🧠 ANSWER ✔✔double covalent bond
the notation used to represent atoms and bonding - 🧠 ANSWER
✔✔structural formula
2026 Exam Questions and Verified
Answers | Already Graded A+
organisms are composed of _______________ - 🧠 ANSWER ✔✔matter
anything that takes up space and has mass - 🧠 ANSWER ✔✔matter
a substance that cannot be broken down to other substances by chemical
reactions
example: hydrogen - 🧠 ANSWER ✔✔element
a substance consisting of two or more elements in a fixed ratio
,example: water (H2O) - 🧠 ANSWER ✔✔compound
the smallest unit of matter that still retains the properties of an element - 🧠
ANSWER ✔✔atom
atoms are composed of subatomic particles. list the subatomic particles
and their charges - 🧠 ANSWER ✔✔neutron (no charge), proton (positive
charge), electron (negative charge)
neutrons and protons form the ____________ - 🧠 ANSWER ✔✔atomic
nucleus
neutron mass and proton mass are almost identical and are measured in
____________ - 🧠 ANSWER ✔✔daltons
the number of protons in an element's nucleus - 🧠 ANSWER ✔✔atomic
number
the sum of protons plus neutrons in the nucleus of an element - 🧠 ANSWER
✔✔mass number
the atom's total mass, can be approximated by the mass number - 🧠
ANSWER ✔✔atomic mass
,two atoms of an element that differ in the number of neutrons - 🧠 ANSWER
✔✔isotope
isotopes that decay spontaneously, giving off particles and energy - 🧠
ANSWER ✔✔radioactive isotopes
an electron's state of potential energy is called its _________ - 🧠 ANSWER
✔✔energy level/electron shell
1st shell max: 2 electrons
2nd shell max: 8 electrons
3rd shell max: 8 electrons
when electrons move from a lower energy level to a higher energy level,
energy is _________ - 🧠 ANSWER ✔✔absorbed
when electrons move from a higher energy level to a lower energy level,
energy is ________ - 🧠 ANSWER ✔✔lost
electrons located in the outermost, or valence shell; chemical behavior of
the atom is determined by these electrons - 🧠 ANSWER ✔✔valence
electrons
COPYRIGHT©NINJANERD 2025/2026. YEAR PUBLISHED 2025. COMPANY REGISTRATION NUMBER: 619652435. TERMS OF USE. PRIVACY
STATEMENT. ALL RIGHTS RESERVED
3
, electrons with a full valence shell are ____________ - 🧠 ANSWER
✔✔chemically inert
atoms with __________ valence shells can share or transfer valence
electrons with certain other atoms - 🧠 ANSWER ✔✔incomplete
attractions that hold atoms close together - 🧠 ANSWER ✔✔chemical bonds
the sharing of a pair of valence electrons by 2 atoms; the shared electrons
count as a part of each atom's valence shell
example: H2 hydrogen molecule - 🧠 ANSWER ✔✔covalent bond
consists of two or more atoms held together by covalent bonds
example: water (H2O)
2 hydrogen atoms + 1oxygen atom - 🧠 ANSWER ✔✔molecule
the sharing of one pair of valence electrons - 🧠 ANSWER ✔✔single
covalent bond
the sharing of two pairs of electrons - 🧠 ANSWER ✔✔double covalent bond
the notation used to represent atoms and bonding - 🧠 ANSWER
✔✔structural formula
