Biochemistry CHEM 210 Exam Prep Test
Bank – A Review of 350 Latest Real Exam
Questions and Correct Answers/ CHEM
210 Exam Preparation Test Bank (Newest
)
SECTION I: Foundations of Biochemistry & Water Properties (Questions 1-40)
1. What is biochemistry?
A. The study of inorganic compounds
B. The study of non-carbon compounds
C. The chemistry of life
D. The study of metals and minerals
Correct Answer: C
Rationale: Biochemistry is the branch of science that explores the chemical processes within
and related to living organisms .
2. Which element is considered the "superglue of the chemical world"?
A. Oxygen
B. Nitrogen
C. Carbon
D. Hydrogen
Correct Answer: C
Rationale: Carbon is unique because it can form four stable covalent bonds, allowing it to serve
as the central building block for countless complex organic molecules and form diverse
structures including long chains, rings, and multiple bonds .
,3. How many of the 90 naturally occurring elements are found in living organisms?
A. All 90
B. More than 50
C. Less than 30
D. Exactly 45
Correct Answer: C
Rationale: Fewer than 30 naturally occurring elements are essential to life. Smaller elements
(nonmetals in the upper right of the periodic table) are favored because they form stable covalent
bonds .
4. What are the four most abundant elements found in living organisms?
A. Carbon, Hydrogen, Oxygen, Nitrogen
B. Carbon, Hydrogen, Oxygen, Sodium
C. Carbon, Nitrogen, Oxygen, Phosphorus
D. Carbon, Hydrogen, Nitrogen, Sulfur
Correct Answer: A
Rationale: These four elements make up approximately 96% of the mass of most living
organisms. They are considered "bulk elements" and form the backbone of all major
biomolecules .
5. Which property of carbon allows it to form diverse structures such as chains and rings?
A. It has two valence electrons
B. It is a noble gas
C. It has four valence electrons
D. It cannot form multiple bonds
Correct Answer: C
Rationale: Carbon's four valence electrons allow it to form up to four covalent bonds, leading to
chains, rings, and multiple bond structures .
,6. What is the bond angle associated with a tetrahedral molecule?
A. 180°
B. 120°
C. 109.5°
D. 107.5°
Correct Answer: C
Rationale: Tetrahedral molecules, such as methane (CH₄), have bond angles of approximately
109.5° .
7. What property of water allows it to act as an effective solvent for ionic compounds?
A. Low heat capacity
B. Nonpolarity
C. Polarity and hydrogen bonding
D. High viscosity
Correct Answer: C
Rationale: Water's polarity allows it to surround and stabilize ions. The partial negative charge
on oxygen attracts positive ions (cations), while the partial positive charge on hydrogen attracts
negative ions (anions), effectively dissolving ionic compounds .
8. Which statement correctly describes water's role in biological systems?
A. Water is a poor solvent for charged molecules
B. Water can make up to 70-85% of a living organism's mass
C. Water is considered a non-polar solvent
D. Water molecules cannot form hydrogen bonds
Correct Answer: B
Rationale: Water is known as the "medium of life." In many organisms, water constitutes 70-
85% of total mass. Its polar nature allows it to serve as an excellent solvent for ions and polar
molecules .
, 9. What is pH if the hydrogen ion concentration is 1 × 10⁻⁷ M?
A. 1
B. 5
C. 7
D. 14
Correct Answer: C
Rationale: pH is defined as the negative logarithm of the hydrogen ion concentration: pH = -
log[H⁺]. For [H⁺] = 1 × 10⁻⁷ M, pH = 7 (neutral) .
10. What happens to pH when [H⁺] increases tenfold?
A. Increases by 1
B. Decreases by 1
C. Remains constant
D. Doubles
Correct Answer: B
Rationale: Because pH = -log[H⁺], a tenfold increase in [H⁺] decreases the pH by exactly one
unit .
11. The H⁺ concentration of a solution is 7.9 × 10⁻¹³ M. What is the pH?
A. 6.70
B. -6.70
C. 12.1
D. 7.90
Correct Answer: C
Rationale: pH = -log(7.9 × 10⁻¹³) ≈ 12.1. This highly basic pH reflects a very low proton
concentration .
Bank – A Review of 350 Latest Real Exam
Questions and Correct Answers/ CHEM
210 Exam Preparation Test Bank (Newest
)
SECTION I: Foundations of Biochemistry & Water Properties (Questions 1-40)
1. What is biochemistry?
A. The study of inorganic compounds
B. The study of non-carbon compounds
C. The chemistry of life
D. The study of metals and minerals
Correct Answer: C
Rationale: Biochemistry is the branch of science that explores the chemical processes within
and related to living organisms .
2. Which element is considered the "superglue of the chemical world"?
A. Oxygen
B. Nitrogen
C. Carbon
D. Hydrogen
Correct Answer: C
Rationale: Carbon is unique because it can form four stable covalent bonds, allowing it to serve
as the central building block for countless complex organic molecules and form diverse
structures including long chains, rings, and multiple bonds .
,3. How many of the 90 naturally occurring elements are found in living organisms?
A. All 90
B. More than 50
C. Less than 30
D. Exactly 45
Correct Answer: C
Rationale: Fewer than 30 naturally occurring elements are essential to life. Smaller elements
(nonmetals in the upper right of the periodic table) are favored because they form stable covalent
bonds .
4. What are the four most abundant elements found in living organisms?
A. Carbon, Hydrogen, Oxygen, Nitrogen
B. Carbon, Hydrogen, Oxygen, Sodium
C. Carbon, Nitrogen, Oxygen, Phosphorus
D. Carbon, Hydrogen, Nitrogen, Sulfur
Correct Answer: A
Rationale: These four elements make up approximately 96% of the mass of most living
organisms. They are considered "bulk elements" and form the backbone of all major
biomolecules .
5. Which property of carbon allows it to form diverse structures such as chains and rings?
A. It has two valence electrons
B. It is a noble gas
C. It has four valence electrons
D. It cannot form multiple bonds
Correct Answer: C
Rationale: Carbon's four valence electrons allow it to form up to four covalent bonds, leading to
chains, rings, and multiple bond structures .
,6. What is the bond angle associated with a tetrahedral molecule?
A. 180°
B. 120°
C. 109.5°
D. 107.5°
Correct Answer: C
Rationale: Tetrahedral molecules, such as methane (CH₄), have bond angles of approximately
109.5° .
7. What property of water allows it to act as an effective solvent for ionic compounds?
A. Low heat capacity
B. Nonpolarity
C. Polarity and hydrogen bonding
D. High viscosity
Correct Answer: C
Rationale: Water's polarity allows it to surround and stabilize ions. The partial negative charge
on oxygen attracts positive ions (cations), while the partial positive charge on hydrogen attracts
negative ions (anions), effectively dissolving ionic compounds .
8. Which statement correctly describes water's role in biological systems?
A. Water is a poor solvent for charged molecules
B. Water can make up to 70-85% of a living organism's mass
C. Water is considered a non-polar solvent
D. Water molecules cannot form hydrogen bonds
Correct Answer: B
Rationale: Water is known as the "medium of life." In many organisms, water constitutes 70-
85% of total mass. Its polar nature allows it to serve as an excellent solvent for ions and polar
molecules .
, 9. What is pH if the hydrogen ion concentration is 1 × 10⁻⁷ M?
A. 1
B. 5
C. 7
D. 14
Correct Answer: C
Rationale: pH is defined as the negative logarithm of the hydrogen ion concentration: pH = -
log[H⁺]. For [H⁺] = 1 × 10⁻⁷ M, pH = 7 (neutral) .
10. What happens to pH when [H⁺] increases tenfold?
A. Increases by 1
B. Decreases by 1
C. Remains constant
D. Doubles
Correct Answer: B
Rationale: Because pH = -log[H⁺], a tenfold increase in [H⁺] decreases the pH by exactly one
unit .
11. The H⁺ concentration of a solution is 7.9 × 10⁻¹³ M. What is the pH?
A. 6.70
B. -6.70
C. 12.1
D. 7.90
Correct Answer: C
Rationale: pH = -log(7.9 × 10⁻¹³) ≈ 12.1. This highly basic pH reflects a very low proton
concentration .
