Unit 1: Chemistry of Life

Question 1

Electronegativity

Answer 1

The property of a molecule that determines its tendency to attract electrons toward itself.

Question 2

The electronegativity difference determines..

Answer 2

..what kind of bond will occur between the atoms.

Question 3

Electronegativity difference of .4 or less is a..

Answer 3

Covalent bond

Question 4

In covalent bonds, the valence electrons are shared..

Answer 4

Equally

Question 5

Electronegativity difference of .5-1.6 is a..

Answer 5

Polar covalent bond

Question 6

In polar covalent bonds, the valence electrons are shared..

Answer 6

Unequally, causing a positive pole and negative pole to be created on the molecule.

Question 7

Electronegativity difference of 1.7 or greater is an..

Answer 7

Ionic bond

Question 8

In ionic bonds, the valence electrons..

Answer 8

Are stolen by the molecule that is more electronegative. The lesser electronegative atom becomes a cation (positive) and the more electronegative becomes an anion (negative). REMEMBER: electrons are NEGATIVE, so the one with more electrons is NEGATIVE

Question 8

The cation and anion will..

Answer 8

Be attracted to one another

Question 9

Symmetrical compounds are..

Answer 9

Non-polar covalent bonds

Question 9

Symmetrical

Answer 9

Electrons are equally distributed

Question 10

Asymmetrical

Answer 10

Electrons are not equally distributed

Question 11

Asymmetrical compounds are..

Answer 11

Polar covalent bonds

Question 12

Water is polar or non-polar?

Answer 12

Polar

Question 13

What does polarity mean for a water molecule?

Answer 13

It displays characteristics that are important for living organisms.

Question 14

Cohesion

Answer 14

Molecules are attracted to the same type of molecule.

Question 15

Water has the ability to be ____ to itself.

Answer 15

Cohesive

Question 16

What is the result of water having the ability to be cohesive to itself?

Answer 16

It participates in hydrogen bonding.

Question 17

What is hydrogen bonding?

Answer 17

An attraction that is between the hydrogen (S+) on one water molecule and the oxygen (S-) on another water molecule.

Question 18

A “thin skin” is created on water as a result of what?

Answer 18

Hydrogen bonding

Question 19

What is this “thin skin” on a water droplet called?

Answer 19

Surface tension

Question 20

Adhesion

Answer 20

Molecules are attracted to a different type of molecule.

Question 21

Water is attracted to non-polar molecules.

Answer 21

False, water is attracted to other polar molecules.

Question 22

Water ___ to those polar molecules ___ than itself.

Answer 22

Sticks, more often

Question 23

Capillary action

Answer 23

The movement of a liquid through a tube due to its attraction to the tube itself.

Question 24

Transpiration

Answer 24

The movement of water from the roots to the leaves in plants.

Question 25

Transpiration results from...

Answer 25

Capillary action

Question 26

Why does transpiration result from capillary action?

Answer 26

This is due to the water molecules evaporating from the leaves.

Question 27

Water has a high ___, which means it has a high boiling point.

Answer 27

Specific heat

Question 28

High specific heat

Answer 28

The amount of energy it takes to heat one gram of a substance up to one degree Celsius.

Question 29

Water has a high specific heat because of...

Answer 29

Hydrogen bonding

Question 30

The more ____ that are displayed within a group of molecules, the ___ it will be to break with heat.

Answer 30

Hydrogen bonds, harder

Question 31

The ____ hydrogen bonds that are present, the ____ the attraction.

Answer 31

More, stronger

Question 32

Water is a good...

Answer 32

Solvent

Question 33

Solvent

Answer 33

When something (in this case water) can dissolve material.

Question 34

Name a reason life requires water.

Answer 34

Ice floats; it becomes less dense when it becomes colder.

Question 35

Dense