Question 1

Which of the following best describes an emergent property in the context of chemical compounds?

Accepted Answer

A property that arises only when elements combine to form a compound, and is not found in the individual elements.

Question 2

Which element is required in minute quantities for normal thyroid gland activity in humans, and what is the recommended daily intake?

Accepted Answer

Iodine (I); 0.15 milligrams per day

Question 3

Given the atomic number of sodium ($$Na) is 11 $$and its mass number is 23, how many neutrons does a neutral sodium atom have?

Accepted Answer

$$12$$ neutrons

Question 4

Which of the following best explains why sodium chloride (NaCl) is edible, even though its constituent elements are a reactive metal and a poisonous gas?

Accepted Answer

The combination of sodium and chlorine results in a compound with emergent properties different from those of the individual elements.

Question 5

Which subatomic particle is responsible for the chemical behavior of an atom?

Accepted Answer

Electrons

Question 6

A radioactive isotope of carbon, $$^{14}C$$, has 6 protons. How many neutrons does it have?

Accepted Answer

$$8$$ neutrons

Question 7

Which statement correctly describes the relationship between electron shells and potential energy?

Accepted Answer

Electrons in shells farther from the nucleus have higher potential energy.

Question 8

Which of the following best describes a covalent bond?

Accepted Answer

A bond formed by the sharing of a pair of valence electrons between two atoms.

Question 9

Water ($$H_2O) is a $$polar molecule. Which feature of its covalent bonds causes this polarity?

Accepted Answer

Oxygen is more electronegative than hydrogen, causing unequal sharing of electrons.

Question 10

Which type of chemical bond is primarily responsible for the structure of DNA and the folding of proteins?

Accepted Answer

Hydrogen bonds

Question 11

A gecko can climb smooth walls due to thousands of weak interactions between its toe hairs and the surface. What type of interaction is this?

Accepted Answer

Van der Waals interactions

Question 12

Which of the following is true about elements with a full valence shell?

Accepted Answer

They are chemically inert.

Question 13

Which equation correctly represents the conservation of matter in the reaction: $$Fe_2O_3 + C \rightarrow Fe + CO$$?

Accepted Answer

$$Fe_2O_3 + 3C \rightarrow 2Fe + 3CO$$

Question 14

Which of the following best describes the difference between a molecule and an ionic compound?

Accepted Answer

A molecule is held together by covalent bonds, while an ionic compound is held together by ionic bonds.

Question 15

Which of the following elements makes up the largest percentage of body mass in humans?

Accepted Answer

Oxygen

Question 16

If an atom has 8 electrons, how are they distributed among the first, second, and third electron shells?

Accepted Answer

2 in the first shell, 6 in the second shell, 0 in the third shell

Question 17

Which of the following is a trace element required by all organisms?

Accepted Answer

Iron (Fe)

Question 18

Which of the following best describes a hydrogen bond?

Accepted Answer

A weak attraction between a hydrogen atom covalently bonded to an electronegative atom and another electronegative atom.

Question 19

Which property of water is most directly related to its ability to dissolve ionic compounds like NaCl?

Accepted Answer

Its polar covalent bonds and partial charges

Question 20

Which of the following indirectly determines the number and type of bonds an atom can form?

Accepted Answer

Number of valence electrons

Chapter 2: The Chemical Context of Life – Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards