Question 1

Which of the following best explains why atoms are electrically neutral in their standard state?

Accepted Answer

Because the number of protons equals the number of electrons.

Question 2

A nitrogen atom has 7 protons and 7 neutrons. What is its atomic number and mass number?

Accepted Answer

Atomic number = 7, Mass number = 14

Question 3

Which of the following statements correctly describes a covalent bond?

Accepted Answer

A covalent bond is formed when two atoms share one or more pairs of electrons.

Question 4

Which of the following best describes a polar covalent bond?

Accepted Answer

A bond in which electrons are shared unequally, resulting in partial charges on the atoms.

Question 5

What determines the reactivity of an atom?

Accepted Answer

The number of electrons in the valence shell.

Question 6

Which of the following is an example of an ionic bond?

Accepted Answer

NaCl, where sodium donates an electron to chlorine.

Question 7

How many electrons are shared in a single covalent bond?

Accepted Answer

2

Question 8

Which of the following best describes a hydrogen bond?

Accepted Answer

An attraction between a hydrogen atom with a partial positive charge and another atom with a partial negative charge.

Question 9

Given the molecular formula $$C_6H_{12}O_6$, how many total atoms are present in one molecule of glucose?

Accepted Answer

$$6 + 12 + 6 = 24$$ atoms

Question 10

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

Accepted Answer

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

Question 11

A student is given a diagram showing two atoms sharing two pairs of electrons. What type of bond is this?

Accepted Answer

A double covalent bond

Question 12

Which of the following elements is NOT one of the four that make up 96% of living matter?

Accepted Answer

Magnesium (Mg)

Question 13

If an atom has an atomic number of 12 and a mass number of 24, how many neutrons does it have?

Accepted Answer

$$24 - 12 = 12$$ neutrons

Question 14

Which of the following best describes the difference between ionic and covalent bonds?

Accepted Answer

Ionic bonds involve the transfer of electrons, while covalent bonds involve the sharing of electrons.

Question 15

Which of the following would most likely form a non-polar covalent bond?

Accepted Answer

Two atoms of the same element, such as $$O_2$$

Question 16

A molecule is held together by one, two, or three solid lines in its structural formula. What type of bond do these lines represent?

Accepted Answer

Covalent bonds

Question 17

Which of the following scenarios best illustrates the formation of a hydrogen bond?

Accepted Answer

A water molecule's hydrogen atom is attracted to the oxygen atom of a neighboring water molecule.

Question 18

Which of the following is the best explanation for why the nucleus of an atom has a positive charge?

Accepted Answer

Because it contains protons, which are positively charged.

Question 19

Which of the following best describes an emergent property of a compound?

Accepted Answer

A property that arises when two or more elements combine, which is not present in the individual elements.

Question 20

A patient is diagnosed with a genetic disorder that affects the number of electrons in the valence shell of their cells' atoms. Which of the following is most likely to be affected as a result?

Accepted Answer

The chemical reactivity of the atoms in their cells.

Chapter 2: The Chemical Context of Life – Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard