2-1 BIO-1010 Study Guide

Question 1

What are the three basic types of subatomic particles in an atom?

Answer 1

Protons, neutrons, and electrons.

Question 2

How are protons, electrons, and neutrons different in terms of their mass, charge, and location within an atom?

Answer 2

Protons: Positive charge, in nucleus, heavy. Neutrons: No charge, in nucleus, similar mass to protons. Electrons: Negative charge, in clouds, very light mass.

Question 3

What is meant by isotopes of an atom?

Answer 3

Atoms with the same number of protons but different numbers of neutrons.

Question 4

What is the half-life of a radioactive isotope?

Answer 4

The time for half of the radioactive atoms in a sample to decay.

Question 5

What does the octet rule tell us about electrons in an atom?

Answer 5

Atoms are stable when they have 8 electrons in their outer shell.

Question 6

How does an atom become a positive or negative ion?

Answer 6

By losing electrons (positive) or gaining electrons (negative).

Question 7

What is an ionic bond?

Answer 7

A bond formed between a positive ion and a negative ion.

Question 8

What does pH measure?

Answer 8

The concentration of hydrogen ions (H⁺) in a solution.

Question 9

What is the pH of a neutral solution (distilled water)?

Answer 9

pH 7.

Question 10

What is a covalent bond?

Answer 10

A bond where two atoms share a pair of electrons.

Question 11

What is the difference between non-polar and polar covalent bonds?

Answer 11

Non-polar: Electrons shared equally. Polar: Electrons shared unequally.

Question 12

Why do hydrogen bonds form, and why is water so good at this?

Answer 12

Hydrogen bonds form between slight positive and negative regions; water is polar, making it good at forming hydrogen bonds.

Question 13

__________ is everything that has mass (weight) and takes up space.

Answer 13

Matter

Question 14

Matter is made up of about 100 pure substances called __________.

Answer 14

Elements

Question 15

The smallest bit of any element is called an __________.

Answer 15

Atom

Question 16

__________ have a positive charge and are found in the atom’s nucleus.

Answer 16

Protons

Question 17

__________ have no charge and are also found in the atom’s nucleus.

Answer 17

Neutrons

Question 18

__________ are found in “clouds” surrounding the nucleus and have a negative charge.

Answer 18

Electrons

Question 19

The number of __________ in an atom determines what type of element it is.

Answer 19

Protons

Question 20

Different __________ of an atom have the same number of protons but different numbers of neutrons.

Answer 20

Isotopes

Question 21

The cloud or shell closest to an atom’s nucleus has room for only __________ electrons.

Answer 21

2

Question 22

The next two shells farther out have room for __________ electrons.

Answer 22

8

Question 23

An atom of sulfur (atomic number 16) has __________ electrons in its first shell, __________ electrons in its second shell, and __________ electrons in its third (outer) shell.

Answer 23

2, 8, 6

Question 24

When an atom such as potassium loses the only electron in its outer shell, it becomes a __________.

Answer 24

Positive ion

Question 25

When an atom such as fluorine gains one electron in order to fill its outer electron shell, it becomes a __________.

Answer 25

Negative ion

Question 26

An __________ is a bond between a positive ion and a negative ion.

Answer 26

Ionic bond

Question 27

__________ is a measure of the hydrogen ion concentration of a solution.

Answer 27

pH

Question 28

What is the difference between a solution, a solvent, and a solute?

Answer 28

A solution is a mixture, the solvent is the substance in which something is dissolved, and the solute is the substance being dissolved.

Question 29

What is the definition of diffusion?

Answer 29

The movement of particles from an area of high concentration to an area of low concentration.

Question 30

What is osmosis?

Answer 30

The diffusion of water through a selectively permeable membrane.

Question 31

What is the difference between passive transport and active transport?

Answer 31

Passive transport does not require energy, while active transport does require energy.

Question 32

Approximately how many millimeters are there in one inch?

Answer 32

25.4 millimeters.

Question 33

One degree change in degrees centigrade is equal to about how many degrees change in degrees Fahrenheit?

Answer 33

1.8 degrees Fahrenheit.

Question 34

About how many milliliters are there in one liquid ounce?

Answer 34

About 29.6 milliliters.

Question 35

About how many grams are there in one ounce of weight?

Answer 35

About 28.35 grams.