Basic Chemistry Concepts for Biochemistry: Master the Fundamentals

Question 1

Which intermolecular force is responsible for the attraction between two polar molecules?

Accepted Answer

Dipole-dipole interaction

Answer

Ionic bonding

Answer

Covalent bonding

Answer

Van der Waals forces

Question 2

Which of the following statements accurately describes the nature of covalent bonds?

Accepted Answer

Electrons are distributed equally between atoms, resulting in the formation of shared electron pairs.

Answer

Formed between atoms with significant differences in electronegativity, leading to the transfer of electrons.

Answer

Typically involve the attraction between oppositely charged ions, creating highly polar molecules.

Answer

Characterized by the presence of completely nonpolar molecules due to the absence of any charge separation.

Question 3

Which of the following factors is most influential in determining the strength of intermolecular forces between molecules?

Accepted Answer

Molecular polarity

Answer

Molecular size

Answer

Number of valence electrons

Answer

Atomic mass

Question 4

In a chemical compound formed between a positively charged sodium ion (Na+) and a negatively charged chloride ion (Cl-), what type of bond is present?

Accepted Answer

Ionic bond

Answer

Covalent bond

Answer

Metallic bond

Answer

Hydrogen bond

Question 5

The electronic configuration of an element is 2, 8, 4. What is the atomic number of this element?

Accepted Answer

16

Answer

14

Answer

18

Answer

20

Question 6

Which of the following is not considered a fundamental particle of matter?

Accepted Answer

Photon

Answer

Proton

Answer

Neutron

Answer

Electron

Question 7

What is the expected pH of a 0.01 M solution of a strong acid?

Accepted Answer

1

Answer

2

Answer

7

Answer

14

Question 8

Which of the following accurately defines a buffer solution?

Accepted Answer

A solution that resists changes in pH when small amounts of acid or base are added.

Answer

A solution with a high concentration of hydrogen ions, resulting in a low pH.

Answer

A solution with a low concentration of hydroxide ions, leading to a high pH.

Answer

A solution that undergoes a chemical reaction to neutralize added acids or bases.

Question 9

What is the primary role of enzymes in biochemical reactions?

Accepted Answer

To lower the activation energy barrier, facilitating faster reaction rates.

Answer

To increase the activation energy barrier, making reactions less likely to occur.

Answer

To act as reactants in the reactions, getting consumed in the process.

Answer

To prevent reactions from taking place altogether.

Question 10

Which of the following is NOT a fundamental subatomic particle?

Accepted Answer

Nucleus

Answer

Proton

Answer

Neutron

Answer

Electron

Question 11

Which type of chemical bond results from the attraction between oppositely charged ions?

Accepted Answer

Ionic bond

Answer

Covalent bond

Answer

Metallic bond

Answer

Hydrogen bond

Question 12

A solution with a [H+] concentration of 1 x 10^-7 M has a pH of:

Accepted Answer

1

Answer

7

Answer

10

Answer

14

Question 13

Which of the following is a characteristic of a buffer solution?

Accepted Answer

Can resist changes in pH upon addition of small amounts of acid or base

Answer

Has a high concentration of either H+ or OH-

Answer

Is a strong acid

Answer

Is a weak base

Question 14

What is the hybridization of the carbon atom in ethane (C2H6)?

Accepted Answer

sp3

Answer

sp

Answer

sp2

Answer

sp3d

Question 15

Which of the following reactions releases heat energy?

Accepted Answer

Combustion of methane

Answer

Dissolution of salt in water

Answer

Melting of ice

Answer

Evaporation of water

Question 16

Which of the following carbohydrates can undergo mutarotation?

Accepted Answer

Glucose

Answer

Sucrose

Answer

Lactose

Answer

Starch

Question 17

The primary function of enzymes in biochemical reactions is to:

Accepted Answer

Decrease the activation energy of the reaction

Answer

Increase the activation energy of the reaction

Answer

Change the products of the reaction

Answer

Increase the temperature of the reaction

Question 18

How does the number of protons in an atom affect its electron configuration and chemical properties?

Accepted Answer

The number of protons determines the number of electrons needed for a balanced charge, influencing the electron configuration.

Answer

The number of protons has no impact on electron configuration.

Answer

The number of protons determines the number of neutrons in an atom.

Answer

The number of protons does not influence the chemical properties of the element.

Question 19

How do the forces between molecules affect a substance's melting and boiling points?

Accepted Answer

Stronger forces between molecules result in higher melting and boiling points.

Answer

The forces between molecules have no significant impact on a substance's melting or boiling point.

Answer

The forces between molecules solely determine if a substance is a solid, liquid, or gas at room temperature.

Answer

The forces between molecules are solely responsible for changes between solid, liquid, and gas states.

Question 20

Which of the following is the correct electron configuration for nitrogen?

Accepted Answer

1s²2s²2p⁵

Answer

1s²2s³2p⁴

Answer

1s²2s²2p³

Answer

1s²2s⁴2p³

Question 21

What type of chemical bond forms when atoms share electrons?

Accepted Answer

Covalent bond

Answer

Ionic bond

Answer

Hydrogen bond

Answer

Van der Waals force

Question 22

Which of the following intermolecular forces is the weakest?

Accepted Answer

London dispersion forces

Answer

Hydrogen bonding

Answer

Dipole-dipole interactions

Answer

Ion-dipole interactions

Question 23

What is the pH of a solution with a [H⁺] of 1 x 10^-8 M?

Accepted Answer

8

Answer

2

Answer

7

Answer

12

Question 24

Which of the following is a key characteristic of a covalent bond?

Accepted Answer

Forms between atoms of differing electronegativity

Answer

Involves the transfer of electrons

Answer

Results in the formation of ions

Answer

Is typically non-directional

Question 25

What is the hybridization state of the carbon atom in methane?

Accepted Answer

sp3

Answer

sp

Answer

sp2

Answer

sp3d

Question 26

Which substance listed below is expected to exhibit the strongest intermolecular forces?

Accepted Answer

H2O

Answer

CH4

Answer

NH3

Answer

HF

Question 27

Calculate the molar mass of NaCl (sodium chloride).

Accepted Answer

58.44 g/mol

Answer

22.99 g/mol

Answer

35.45 g/mol

Answer

70.90 g/mol

Question 28

Which of the following pairs does NOT form a buffer solution?

Accepted Answer

Hydrochloric acid and sodium hydroxide

Answer

Acetic acid and sodium acetate

Answer

Carbonic acid and sodium carbonate

Answer

Ammonium hydroxide and ammonium chloride

Question 29

What is the pKa of a weak acid with a dissociation constant of 1 x 10^-5?

Accepted Answer

5

Answer

2

Answer

7

Answer

10

Question 30

Chemical equilibrium is a crucial concept in chemistry. What significant role does the equilibrium constant play in understanding chemical reactions?

Accepted Answer

Quantifies the extent to which a reaction proceeds

Answer

Predicts the direction in which a reaction will proceed

Answer

Indicates whether a reaction is spontaneous or non-spontaneous

Answer

Determines the rate at which a reaction occurs

Question 31

Explain the impact of resonance on the chemical properties and bonding of a molecule.

Accepted Answer

Resonance can enhance molecular stability by distributing charge more evenly.

Accepted Answer

Resonance may weaken specific bonds by lowering their bond order.

Answer

Resonance occurs exclusively in molecules with alternating double and single bonds.

Answer

Resonance has no influence on the chemical reactivity of a molecule.

Question 32

Which of these is NOT an intermolecular force?

Accepted Answer

Covalent bonding

Answer

Hydrogen bonding

Answer

Dipole-dipole interactions

Answer

London dispersion forces

Question 33

Rank the following intermolecular forces from strongest to weakest: hydrogen bonding, dipole-dipole interactions, and London dispersion forces.

Accepted Answer

Hydrogen bonding > dipole-dipole interactions > London dispersion forces

Answer

Dipole-dipole interactions > hydrogen bonding > London dispersion forces

Answer

London dispersion forces > dipole-dipole interactions > hydrogen bonding

Answer

London dispersion forces > hydrogen bonding > dipole-dipole interactions

Question 34

Which type of chemical bond involves the electrostatic attraction between oppositely charged ions?

Accepted Answer

Ionic bond

Answer

Covalent bond

Answer

Van der Waals force

Answer

Metallic bond

Question 35

Which of the following molecules has a polar covalent bond?

Accepted Answer

H-Cl

Answer

Na-Cl

Answer

C-C

Answer

H-H

Question 36

What is the hybridization of the central carbon atom in methane (CH₄)?

Accepted Answer

sp³

Answer

sp²

Answer

sp³d

Answer

sp

Question 37

Which of the following intermolecular forces is the weakest?

Accepted Answer

London dispersion forces

Answer

Ionic bonding

Answer

Dipole-dipole interactions

Answer

Hydrogen bonding

Question 38

What is the pH of a 0.01 M solution of a strong acid?

Accepted Answer

2

Answer

14

Answer

10

Answer

7

Question 39

Which of the following reactions is an example of a redox reaction?

Accepted Answer

2Na + 2H₂O → 2NaOH + H₂

Answer

CH₄ + 2O₂ → CO₂ + 2H₂O

Answer

NaCl + AgNO₃ → AgCl + NaNO₃

Answer

CaCO₃ → CaO + CO₂

Question 40

Which type of chemical bond is formed by the sharing of electron pairs between atoms?

Accepted Answer

Covalent bond

Answer

Hydrogen bond

Answer

Metallic bond

Answer

Ionic bond

Question 41

Which of the following intermolecular forces is generally the strongest?

Accepted Answer

Hydrogen bond

Answer

London dispersion force

Answer

Ion-dipole interaction

Answer

Dipole-dipole interaction

Question 42

Which of the following solutions acts as a buffer?

Accepted Answer

A solution containing a weak acid and its conjugate base

Answer

A solution containing only a weak acid

Answer

A solution containing only a strong acid

Answer

A solution containing a strong acid and its conjugate base

Question 43

What is the molar mass of sodium chloride (NaCl)?

Accepted Answer

58.44 g/mol

Answer

35.45 g/mol

Answer

105.89 g/mol

Answer

22.99 g/mol

Question 44

What is the sign of the enthalpy change (ΔH) for an exothermic reaction?

Accepted Answer

Negative

Answer

Cannot be determined

Answer

Zero

Answer

Positive

Question 45

Which of the following describes a spontaneous process?

Accepted Answer

A process that occurs without requiring external energy input

Answer

A process that requires external energy input to occur

Answer

A process that is reversible

Answer

A process that happens very quickly

Question 46

What does the equilibrium constant (Keq) represent for a reaction at equilibrium?

Accepted Answer

The ratio of product concentrations to reactant concentrations at equilibrium

Answer

The change in free energy of the reaction

Answer

The ratio of reactant concentrations to product concentrations at equilibrium

Answer

The rate of the forward reaction