AICE Marine Science Exam 2026/2027 | AS & A Level |
Complete Practice Questions, Answers & Detailed
Explanations
SECTION 1 — WATER
1. Which statement best explains why water is liquid at typical ocean
temperatures?
A. Water molecules contain ionic bonds
B. Hydrogen bonding occurs between water molecules
C. Water contains dissolved salts
D. Oxygen atoms have no electrons
Correct Answer: B. Hydrogen bonding occurs between water
molecules
Rationale: Hydrogen bonds between water molecules create strong
intermolecular attractions. These attractions increase the energy
required for water molecules to separate, helping water remain liquid
over a relatively broad temperature range.
2. During melting of sea ice, what happens to the particles?
A. They stop moving
B. They move farther apart and gain freedom of movement
C. They become chemically bonded into new substances
D. They lose all kinetic energy
,Correct Answer: B. They move farther apart and gain freedom of
movement
Rationale: Melting changes water from a solid to a liquid. The particles
gain kinetic energy and are able to move more freely while remaining
relatively close together.
3. Which particles are found in the nucleus of an atom?
A. Electrons and ions
B. Protons and neutrons
C. Electrons and protons
D. Neutrons and electrons
Correct Answer: B. Protons and neutrons
Rationale: The nucleus contains positively charged protons and
uncharged neutrons. Electrons occupy shells surrounding the nucleus.
4. Which particle has a negative charge?
A. Proton
B. Neutron
C. Electron
D. Nucleus
Correct Answer: C. Electron
Rationale: Electrons have a negative electrical charge. Protons are
positive and neutrons have no electrical charge.
,5. What type of bonding occurs within a water molecule?
A. Ionic
B. Metallic
C. Covalent
D. Hydrogen
Correct Answer: C. Covalent
Rationale: The hydrogen and oxygen atoms in a water molecule share
electron pairs, forming covalent bonds. Hydrogen bonds occur between
separate water molecules.
6. Which substance is a covalent molecule?
A. Sodium chloride
B. Water
C. Sodium ion
D. Chloride ion
Correct Answer: B. Water
Rationale: Water consists of atoms joined by covalent bonds. Sodium
chloride forms an ionic lattice rather than discrete covalent molecules.
7. Why can many ionic compounds dissolve in seawater?
A. Water is non-polar
B. Water molecules interact with charged ions
C. Water destroys all chemical bonds
D. Ions become covalent molecules
, Correct Answer: B. Water molecules interact with charged ions
Rationale: Water is polar, allowing its partially charged regions to
interact with ions. This can separate ions from an ionic lattice and keep
them dispersed in solution.
8. Which property of water is especially important in moderating
marine temperatures?
A. High specific heat capacity
B. Low density as a solid only
C. Low boiling point
D. Lack of polarity
Correct Answer: A. High specific heat capacity
Rationale: Water can absorb substantial quantities of thermal energy
with relatively small temperature changes. This helps oceans moderate
coastal and global temperatures.
9. Why does ice float on liquid water?
A. Ice contains salt
B. Ice is less dense than liquid water
C. Ice has no hydrogen bonds
D. Ice contains more oxygen atoms
Correct Answer: B. Ice is less dense than liquid water
Complete Practice Questions, Answers & Detailed
Explanations
SECTION 1 — WATER
1. Which statement best explains why water is liquid at typical ocean
temperatures?
A. Water molecules contain ionic bonds
B. Hydrogen bonding occurs between water molecules
C. Water contains dissolved salts
D. Oxygen atoms have no electrons
Correct Answer: B. Hydrogen bonding occurs between water
molecules
Rationale: Hydrogen bonds between water molecules create strong
intermolecular attractions. These attractions increase the energy
required for water molecules to separate, helping water remain liquid
over a relatively broad temperature range.
2. During melting of sea ice, what happens to the particles?
A. They stop moving
B. They move farther apart and gain freedom of movement
C. They become chemically bonded into new substances
D. They lose all kinetic energy
,Correct Answer: B. They move farther apart and gain freedom of
movement
Rationale: Melting changes water from a solid to a liquid. The particles
gain kinetic energy and are able to move more freely while remaining
relatively close together.
3. Which particles are found in the nucleus of an atom?
A. Electrons and ions
B. Protons and neutrons
C. Electrons and protons
D. Neutrons and electrons
Correct Answer: B. Protons and neutrons
Rationale: The nucleus contains positively charged protons and
uncharged neutrons. Electrons occupy shells surrounding the nucleus.
4. Which particle has a negative charge?
A. Proton
B. Neutron
C. Electron
D. Nucleus
Correct Answer: C. Electron
Rationale: Electrons have a negative electrical charge. Protons are
positive and neutrons have no electrical charge.
,5. What type of bonding occurs within a water molecule?
A. Ionic
B. Metallic
C. Covalent
D. Hydrogen
Correct Answer: C. Covalent
Rationale: The hydrogen and oxygen atoms in a water molecule share
electron pairs, forming covalent bonds. Hydrogen bonds occur between
separate water molecules.
6. Which substance is a covalent molecule?
A. Sodium chloride
B. Water
C. Sodium ion
D. Chloride ion
Correct Answer: B. Water
Rationale: Water consists of atoms joined by covalent bonds. Sodium
chloride forms an ionic lattice rather than discrete covalent molecules.
7. Why can many ionic compounds dissolve in seawater?
A. Water is non-polar
B. Water molecules interact with charged ions
C. Water destroys all chemical bonds
D. Ions become covalent molecules
, Correct Answer: B. Water molecules interact with charged ions
Rationale: Water is polar, allowing its partially charged regions to
interact with ions. This can separate ions from an ionic lattice and keep
them dispersed in solution.
8. Which property of water is especially important in moderating
marine temperatures?
A. High specific heat capacity
B. Low density as a solid only
C. Low boiling point
D. Lack of polarity
Correct Answer: A. High specific heat capacity
Rationale: Water can absorb substantial quantities of thermal energy
with relatively small temperature changes. This helps oceans moderate
coastal and global temperatures.
9. Why does ice float on liquid water?
A. Ice contains salt
B. Ice is less dense than liquid water
C. Ice has no hydrogen bonds
D. Ice contains more oxygen atoms
Correct Answer: B. Ice is less dense than liquid water