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CHEM120 - Exam 3 Review Questions
and Answers (100% Correct
Answers) Already Graded A+
Isotopes Ans: They have different number of neutrons, some
have unstable nuclei. They undergo radioactive decay.
© 2026 Assignment
Nucleons Ans: In nuclear reactions, we balance _________
instead of atoms.
Guru01 - Stuvia
Expert
Alpha Decay Ans: Gives off an alpha particle which is he
equivalent of a He (helium). The atomic number decreases by 2
and the nucleon (mass number) number by 4.
Electron Beta Decay Ans: A neutron is converted to a proton
that remains and an electron is ejected. Atomic number will
increase by 1 because the neutron is converted to a proton.
Mass number will not change because it is the total number of
protons/neutrons.
Positron Emission Ans: A second type of beta decay, a proton
is changing to a neutron. The atomic number will decrease by
1. The mass number will be unchanged.
Electron capture Ans: An electron combines with a proton to
produce a neutron. The atomic number will decrease by 1 as
we are losing proton. The mass number will not change.
Half-life Ans: The amount of time required for radioactivity
to decay to half its original amount.
, 2
Carbohydrates Ans: One of the major biomolecules. Can be
aldehyde or ketone. Form ring structures in the body. Can be
simple or complex.
Glycosidic bonds Ans: Individual sugar molecules are held
together by what?
Triglyceride Ans: The three fatty acids attached to a glycerol
is know as what?
© 2026 Assignment
Amine; carboxylic acid Ans: Amino acids has ____________ and
__________________ terminus.
Guru01 - Stuvia
Peptide bonds Ans: Amino acids linked via what?
Expert
Polypeptide Ans: A long chain of amino acids.
Nucleic Acids Ans: They are group of biomolecules that carry
genetic information. They are present in the cell nucleus and
cytoplasm.
Deoxyribonucleic acid (DNA) Ans: Occurs in the cell nucleus
and has a molar mass of 106 to 109g/mol.
Ribonucleic acid (RNA) Ans: It is found in the cytoplasm and
has a molar mass of 25,000 to 106g/mol.
Messenger RNA (mRNA) Ans: It carries the DNA code to
ribosomes, the sites in the cytoplasm of protein synthesis.
Helicase Ans: It unwinds DNA.
RNA polymerase Ans: It makes the complimentary RNA
strand from DNA.
CHEM120 - Exam 3 Review Questions
and Answers (100% Correct
Answers) Already Graded A+
Isotopes Ans: They have different number of neutrons, some
have unstable nuclei. They undergo radioactive decay.
© 2026 Assignment
Nucleons Ans: In nuclear reactions, we balance _________
instead of atoms.
Guru01 - Stuvia
Expert
Alpha Decay Ans: Gives off an alpha particle which is he
equivalent of a He (helium). The atomic number decreases by 2
and the nucleon (mass number) number by 4.
Electron Beta Decay Ans: A neutron is converted to a proton
that remains and an electron is ejected. Atomic number will
increase by 1 because the neutron is converted to a proton.
Mass number will not change because it is the total number of
protons/neutrons.
Positron Emission Ans: A second type of beta decay, a proton
is changing to a neutron. The atomic number will decrease by
1. The mass number will be unchanged.
Electron capture Ans: An electron combines with a proton to
produce a neutron. The atomic number will decrease by 1 as
we are losing proton. The mass number will not change.
Half-life Ans: The amount of time required for radioactivity
to decay to half its original amount.
, 2
Carbohydrates Ans: One of the major biomolecules. Can be
aldehyde or ketone. Form ring structures in the body. Can be
simple or complex.
Glycosidic bonds Ans: Individual sugar molecules are held
together by what?
Triglyceride Ans: The three fatty acids attached to a glycerol
is know as what?
© 2026 Assignment
Amine; carboxylic acid Ans: Amino acids has ____________ and
__________________ terminus.
Guru01 - Stuvia
Peptide bonds Ans: Amino acids linked via what?
Expert
Polypeptide Ans: A long chain of amino acids.
Nucleic Acids Ans: They are group of biomolecules that carry
genetic information. They are present in the cell nucleus and
cytoplasm.
Deoxyribonucleic acid (DNA) Ans: Occurs in the cell nucleus
and has a molar mass of 106 to 109g/mol.
Ribonucleic acid (RNA) Ans: It is found in the cytoplasm and
has a molar mass of 25,000 to 106g/mol.
Messenger RNA (mRNA) Ans: It carries the DNA code to
ribosomes, the sites in the cytoplasm of protein synthesis.
Helicase Ans: It unwinds DNA.
RNA polymerase Ans: It makes the complimentary RNA
strand from DNA.
