Wgu C165 Oa Exam Integrated Physical Sciences 2026/2027 | Complete Practice Questions, Verified Answers & Detailed Rationales | Wgu Objective Assessment Study Guide | Graded A+ | Just Released Pdf

WGU C165 OA EXAM INTEGRATED PHYSICAL
SCIENCES 2026/2027 | COMPLETE PRACTICE
QUESTIONS, VERIFIED ANSWERS &
DETAILED RATIONALES | WGU OBJECTIVE
ASSESSMENT STUDY GUIDE | GRADED A+ |
JUST RELEASED PDF
WGU C165 OA EXAM - INTEGRATED PHYSICAL SCIENCES

COMPLETE PRACTICE QUESTIONS WITH VERIFIED ANSWERS & DETAILED
RATIONALES



OVERVIEW

• Comprehensive Study Resource: 200 rigorously organized practice questions
spanning all major exam domains (Chemistry, Physics, Earth Science, Biology, and
Environmental Systems) with detailed explanations and evidence-based rationales
to deepen conceptual understanding.

• Strategic Study Approach: Work through questions sequentially by topic to build
foundational knowledge first, then revisit challenging areas using the detailed
rationales; use this as a self-assessment tool to identify weak points and target
review sessions accordingly.



CHEMISTRY SECTION



1. Which of the following best describes an atom?

A) The smallest unit of an element that retains the properties of that element

B) A particle that contains only protons and neutrons

C) The basic unit of a compound

D) A charged particle with an unequal number of protons and electrons

E) The smallest substance that can be divided by chemical means

,CORRECT ANSWER: A) The smallest unit of an element that retains the
properties of that element

RATIONALE: An atom is defined as the smallest unit of an element that still
maintains the chemical properties of that element. It consists of protons, neutrons,
and electrons. Option B is incorrect because atoms also contain electrons, which
are essential to chemical bonding. Option C describes a molecule, not an atom.
Option D describes an ion, which is a charged atom or group of atoms. Option E is
too broad and could refer to molecules as well. The answer directly reflects the
scientific definition of an atom.



2. What is the maximum number of electrons that can occupy the second
electron shell of an atom?

A) 2 electrons

B) 4 electrons

C) 8 electrons

D) 10 electrons

E) 18 electrons

CORRECT ANSWER: C) 8 electrons

RATIONALE: The electron shell capacity is determined by the formula 2n², where n
is the shell number. For the second shell (n=2), the maximum capacity is 2(2²) = 2(4)
= 8 electrons. Option A represents the first shell capacity. Option B is incorrect.
Option D represents the maximum for the third shell when considering d orbitals.
Option E represents the fourth shell. The second electron shell consists of 2s and
2p subshells, which together hold 8 electrons.



3. Which element is most likely to form a covalent bond?

A) Sodium (Na)

B) Calcium (Ca)

,C) Chlorine (Cl)

D) Potassium (K)

E) Magnesium (Mg)

CORRECT ANSWER: C) Chlorine (Cl)

RATIONALE: Chlorine, a nonmetal in Group 17, has 7 valence electrons and tends
to share electrons to achieve a stable octet, forming covalent bonds. Sodium,
calcium, potassium, and magnesium are all metals (Group 1 and 2 elements) that
tend to lose electrons and form ionic bonds rather than covalent bonds. Nonmetals
generally form covalent bonds by sharing electrons, while metals form ionic bonds
by transferring electrons. Chlorine's high electronegativity makes it highly likely to
participate in covalent bonding.



4. What type of bond is formed between hydrogen and chlorine in HCl?

A) Ionic bond

B) Covalent bond

C) Metallic bond

D) Hydrogen bond

E) Coordinate covalent bond

CORRECT ANSWER: B) Covalent bond

RATIONALE: HCl is a binary compound formed between two nonmetals (hydrogen
and chlorine) through the sharing of electrons, which defines a covalent bond.
While this is technically a polar covalent bond due to the electronegativity
difference, the general classification is covalent. An ionic bond occurs between
metals and nonmetals involving electron transfer. A metallic bond occurs between
metal atoms. A hydrogen bond is an intermolecular force, not a chemical bond
within a molecule. A coordinate covalent bond is a special type of covalent bond
where both electrons come from one atom, which is not the case here.

, 5. Which of the following statements correctly describes a compound?

A) A compound is a pure substance composed of only one type of atom

B) A compound is a mixture of elements that can be separated by physical means

C) A compound is a pure substance composed of two or more elements chemically
bonded in fixed proportions

D) A compound is a gas that results from the combination of two elements

E) A compound is any substance that contains more than one element

CORRECT ANSWER: C) A compound is a pure substance composed of two or
more elements chemically bonded in fixed proportions

RATIONALE: This option accurately defines a compound. A compound must have
elements bonded in fixed (definite) proportions, and it is a pure substance with
consistent properties. Option A describes an element, not a compound. Option B
describes a mixture, which can be separated by physical means, unlike compounds
which require chemical means for separation. Option D is too limiting—compounds
are not restricted to gases. Option E is too broad; a mixture also contains more
than one element but is not a compound. The key distinction is that compounds
have a fixed ratio of elements chemically bonded together.



6. What does the atomic number of an element represent?

A) The total mass of all atoms in the element

B) The number of protons in the nucleus of an atom

C) The number of neutrons in the nucleus of an atom

D) The number of electron shells surrounding the nucleus

E) The number of isotopes that element can form

CORRECT ANSWER: B) The number of protons in the nucleus of an atom

RATIONALE: The atomic number uniquely identifies an element and is defined as
the number of protons in the nucleus. Every atom of an element has the same