HESI (Entrance
Exam) Study Set
Guide Questions
with 100% Correct
Answers 2026-2027
1) What are the most abundant
elements of the human body? -
correct answer=✔✔Carbon, Hydrogen,
Oxygen, Nitrogen
1
,2) 90% of the human body is
composed of just four elements
which are: - correct
answer=✔✔Carbon, Hydrogen,
Oxygen, Nitrogen
3) The smallest unit of an element
that still retains the chemical and
physical properties of the element is
called: - correct answer=✔✔Atom
4) Subatomic particles are: - correct
answer=✔✔Protons (positive),
Neutrons (neutral) and Electrons
(negative)
2
,5) All matter is composed of basic
substances called - correct
answer=✔✔Elements
6) An atom that tells you how many
protons an atom has is called: -
correct answer=✔✔Atomic Number
7) The number of protons and
neutrons is called: - correct
answer=✔✔Mass Number
3
, 8) What is isotope? - correct
answer=✔✔The same element but
different number in protons and
neutrons-Mass Number (protons
plus neutrons) minus Atomic Number
(number of protons) equals the
number of neutrons.
9) What is radioactive isotope? -
correct answer=✔✔Atom whose
nucleus undergoes degeneration
and in the process gives off radiation
4
Exam) Study Set
Guide Questions
with 100% Correct
Answers 2026-2027
1) What are the most abundant
elements of the human body? -
correct answer=✔✔Carbon, Hydrogen,
Oxygen, Nitrogen
1
,2) 90% of the human body is
composed of just four elements
which are: - correct
answer=✔✔Carbon, Hydrogen,
Oxygen, Nitrogen
3) The smallest unit of an element
that still retains the chemical and
physical properties of the element is
called: - correct answer=✔✔Atom
4) Subatomic particles are: - correct
answer=✔✔Protons (positive),
Neutrons (neutral) and Electrons
(negative)
2
,5) All matter is composed of basic
substances called - correct
answer=✔✔Elements
6) An atom that tells you how many
protons an atom has is called: -
correct answer=✔✔Atomic Number
7) The number of protons and
neutrons is called: - correct
answer=✔✔Mass Number
3
, 8) What is isotope? - correct
answer=✔✔The same element but
different number in protons and
neutrons-Mass Number (protons
plus neutrons) minus Atomic Number
(number of protons) equals the
number of neutrons.
9) What is radioactive isotope? -
correct answer=✔✔Atom whose
nucleus undergoes degeneration
and in the process gives off radiation
4
