COMPREHENSIVE SCIENCE REVIEW EXAM
QUESTIONS AND CORRECT ANSWERS
(VERIFIED ANSWERS) PLUS RATIONALES
2026 Q&A | INSTANT DOWNLOAD PDF
1. Which of the following best describes an atom?
a. A particle with a negative charge only
b. The smallest unit of an element that retains its chemical
properties
c. A compound composed of multiple elements
d. A molecule composed of multiple compounds
b
An atom is the smallest unit of an element that retains the
chemical properties of that element.
2. What is the charge of an electron?
a. Positive
b. Neutral
c. Negative
d. Both positive and negative
c
Electrons carry a negative charge and orbit the nucleus of an
atom.
,3. Which subatomic particle determines the identity of an element?
a. Proton
b. Neutron
c. Electron
d. Photon
a
The number of protons in the nucleus defines the element.
4. Water has a high specific heat due to:
a. Ionic bonding
b. Hydrogen bonding
c. Covalent bonding
d. Metallic bonding
b
Hydrogen bonds between water molecules require more energy to
break, giving water a high specific heat.
5. Which of the following is a strong acid?
a. HCl
b. CH3COOH
c. H2CO3
d. NH3
a
Hydrochloric acid (HCl) dissociates completely in water, making it a
strong acid.
6. What type of bond is formed when electrons are shared equally?
a. Ionic
b. Polar covalent
c. Nonpolar covalent
, d. Metallic
c
Nonpolar covalent bonds occur when electrons are shared equally
between atoms.
7. Which organelle is responsible for energy production in a cell?
a. Nucleus
b. Ribosome
c. Mitochondria
d. Golgi apparatus
c
Mitochondria generate ATP through cellular respiration.
8. DNA replication occurs in which phase of the cell cycle?
a. G1 phase
b. S phase
c. G2 phase
d. M phase
b
DNA replication occurs during the S (synthesis) phase of the cell
cycle.
9. Which macromolecule is the main source of energy for cells?
a. Lipids
b. Proteins
c. Carbohydrates
d. Nucleic acids
c
Carbohydrates are the primary energy source due to their easy
conversion to glucose.