Question 1

Which of the following best explains why formic acid has its specific chemical properties?

Accepted Answer

The number and arrangement of its valence electrons

Question 2

How do you determine the number of valence electrons for an atom of oxygen ($$O$$)?

Accepted Answer

Count the electrons in the outermost shell, which is 6 for oxygen

Question 3

Why are valence electrons significant in chemical reactions?

Accepted Answer

They are responsible for the atom's ability to form chemical bonds

Question 4

Which of the following best describes a covalent bond?

Accepted Answer

A bond formed by the sharing of electron pairs between atoms

Question 5

Sodium chloride ($$NaCl) is $$formed by which type of chemical bond?

Accepted Answer

Ionic bond

Question 6

Which statement correctly compares covalent and ionic bonds?

Accepted Answer

Covalent bonds involve the sharing of electrons, while ionic bonds involve the transfer of electrons

Question 7

The molecular shape of a protein is crucial for its function because:

Accepted Answer

It determines the protein's ability to interact with other molecules

Question 8

Which of the following molecules would have a bent shape due to its electron arrangement?

Accepted Answer

Water ($$H_2O)$$

Question 9

A molecule with the formula $$C_2H_6 ($$ethane) has how many covalent bonds?

Accepted Answer

7 single covalent bonds

Question 10

If an atom has 5 valence electrons, how many more electrons does it need to complete its valence shell?

Accepted Answer

3

Question 11

Which of the following is a real-world example of the importance of molecular shape in biology?

Accepted Answer

The ability of enzymes to bind specific substrates

Question 12

Which equation correctly represents the formation of an ionic bond between sodium and chlorine?

Accepted Answer

$$Na + Cl \rightarrow Na^+ + Cl^- \rightarrow NaCl$$

Question 13

Which of the following statements about valence electrons is correct?

Accepted Answer

Valence electrons are responsible for chemical reactivity

Question 14

A patient is exposed to carbon monoxide ($$CO$$), which binds to hemoglobin. Why does $$CO$$ bind so effectively?

Accepted Answer

Because its molecular shape is similar to oxygen, allowing it to fit into the same binding site

Question 15

Which of the following best describes the relationship between molecular shape and biological function?

Accepted Answer

Molecules with similar shapes can have similar biological functions

Question 16

Which of the following is NOT a property determined by the arrangement of valence electrons?

Accepted Answer

The atomic mass of the atom

Question 17

Which of the following is true about ionic bonds in biological systems?

Accepted Answer

They result from the transfer of electrons between atoms

Question 18

A molecule has the formula $$NH_3 ($$ammonia). What is the shape of this molecule and why?

Accepted Answer

Trigonal pyramidal, due to lone pair repulsion on nitrogen

Question 19

Which of the following best explains why water ($$H_2O) is a $$polar molecule?

Accepted Answer

It has a bent molecular shape and unequal sharing of electrons

Question 20

Which of the following is a multi-step process for determining the number of covalent bonds an atom can form?

Accepted Answer

Subtract the number of valence electrons from 8, then use that number to determine bonding capacity

Basic Chemistry: The Chemical Context of Life (Chapter 2) – Key Concepts for Biology

Study Guide - Practice Questions