Chapter 2

Question 1

What is an Ion? And how are they written?

Answer 1

An atom that gave up or gained an electron. written with the chemical symbol and (+) or (-) indicating its charge

Question 2

What is a molecule? And how are they written?

Answer 2

Molecules are formed when atoms share electrons. And they are written as a molecular formula showing the number of atoms of each element (H2O)

Question 3

What are chemical bonds?

Answer 3

The force of attraction that holds atoms of a molecule together

Question 4

What is a valence shell?

Answer 4

The number of electrons in its outermost shell

Question 5

How does a atom decide how it will bond with another atom?

Answer 5

The likelihood that an atom will form a chemical bond with anther atom depends on the number of electrons in its outermost shell

Question 6

What are other types of chemical bonds?

Answer 6

1. Ionic bonds
2. Covalent Bonds
3. Hydrogen Bonds

Question 7

What is a ionic bond?

Answer 7

When an atom loses or gains a valence electron, ions are formed

Question 8

What kind of charged ions are attracted to each other?

Answer 8

Positively charged ions and negatively charged ions are attracted to one another

Question 9

What is Cation?

Answer 9

Positively charged ions that have given up one or more elections (electron donors)

Question 10

What is a Anion?

Answer 10

negatively charged ions that have picked up one ore more electrons that another atom has lost (electron acceptors)

Question 11

What is a covalent bond?

Answer 11

Covalent bonds are formed by the atoms of molecules sharing one, two, or three pairs of their valence electrons

Question 12

What kind of bonds are the strongest chemical bonds in the body?

Answer 12

Covalent bonds

Question 13

Can covalent bonds be nonpolar and polar?

Answer 13

Yes, in a nonpolar covalent bond, atoms share the electrons equally; one atom does not attract the shared electrons more strongly than the other atom

Question 14

What is a polar covalent bond?

Answer 14

Formed by the unequal sharing of electrons between atoms

Question 15

What is a example of a polar covalent bond?

Answer 15

Water molecules.

In a water molecule, oxygen attracts the hydrogen electrons more strongly. Oxygen has greater electronegative as indicated by the negative Greek delta sign

Question 16

What is a hydrogen bond?

Answer 16

A weak bond between two molecules resulting from an electrostatic attraction between a proton in one molecule and a electronegative atom in the other

Question 17

Are hydrogen bonds as strong as covalent bonds?

Answer 17

They are approximately 5% as strong

Question 18

What are inorganic compounds?

Answer 18

Structurally simple molecules that usually lack carbon

Question 19

What are organic compounds?

Answer 19

Molecules that
1. Always contain carbon
2. always have covalent bonds
3. usually contain hydrogen
4. usually are large molecules

Question 20

What is the most important and abundant inorganic compound in all living systems?

Answer 20

Water

Question 21

What is waters most important property?

Answer 21

The polarity of the water, which enables reactants to collide to form products

Question 22

What is a Solvent?

Answer 22

In a solution the solvent dissolves in the solute

Question 23

What does hydrophilic mean?

Answer 23

When substances which contain polar covalent bonds and dissolve in water

Question 24

What does hydrophobic mean?

Answer 24

substance which contain non-polar covalent bonds

Question 25

Is waters heat capacity high or low?

Answer 25

it is high, It can absorb or release a relatively large amount of heat with only a modest change in its own temperature

Question 26

Why can water change its temperature so fast?

Answer 26

The high number of hydrogen ions in water

Question 27

Is waters capacity for vaporization high or low?

Answer 27

It is high. The amount of heat needed to change from liquid to gas requires a large amount of heat.

Question 28

What are 3 common mixtures?

Answer 28

1. Solutions 2. Colloid 3. Suspension

Question 29

What is a solution?

Answer 29

A substance in which the solvent dissolves another substance called the solute. Usually there is more solvent than solute in a solution

Question 30

What is a colloid?

Answer 30

Differs from a solution mainly on the basis of the size of the particles with the particles in the colloid being so large enough to scatter light

Question 31

What is a suspension?

Answer 31

The suspended material may mix with the liquid or suspending medium for some time, but it will eventually settle out.

Question 32

What is range of the pH scale?

Answer 32

0-14

Question 33

What is a neutral pH

Answer 33

7 (water)

Question 34

What is a acidic pH?

Answer 34

pH below 7

Question 35

What is a basic pH?

Answer 35

pH above 7

Question 36

pH is on what kindof scale?

Answer 36

logarithmic scale

Question 37

What is a buffer system?

Answer 37

a solution that resists change in pH when acids or bases are added to it.

Question 38

What do buffer systems accomplish?

Answer 38

Changing strong acids and bases into weak acid and bases

Question 39

What are carbohydrates?

Answer 39

They provide most of the energy needed for life and include sugars, starches, glycogen, and cellulose. Other carbs can function as food

Question 40

Can carbohydrates be converted to other substances?

Answer 40

Yes they can be converted into other substances which are used to build structures and to generate ATP

Question 41

What are the 3 main group of carbs based on their size?

Answer 41

1. Monosaccharides 2. disaccharides 3. Polysaccharides

Question 42

What are lipids?

Answer 42

Like carbs, contain carbon, hydrogen and oxygen; unlike carbs, they do not have a 2:1 ratio of hydrogen to oxygen

Question 43

Do lipids have polar covalent bonds?

Answer 43

They have a few polar covalent bonds

Question 44

If Lipids have few polar bonds, what does that mean?

Answer 44

It means that they are hydrophobic and that they are mostly insoluble in polar solvents like water.

Question 45

What are lipoproteins?

Answer 45

They combine with proteins to transport blood

Question 46

What are proteins?

Answer 46

constructed from combinations of 20 amino acids. And they are the building block for building tissue

Question 47

What are dipeptides?

Answer 47

They are formed from 2 amino acids joined by a covalent bond called a peptide bond

Question 48

What are polypeptide chains?

Answer 48

Formed from 10 to 2000 amino acids

Question 49

What are the levels of structural organization for protein?

Answer 49

1. primary 2. secondary 3. tertiary 4. quaternary

Question 50

What does the resulting shape of the protein influence?

Answer 50

Its ability to recognize and bind to other molecules

Question 51

What is denaturation?

Answer 51

when a protein is in a hostile environment and causes it to lose its characteristic shape and function

Question 52

What is DNA?

Answer 52

forms the genetic code inside each cell and thereby regulates most of the activities that take place in our cells throughout a lifetime

Question 53

What is RNA?

Answer 53

RNA relays instructions from the genes in the cell's nucleus to guide each cells assembly of amino acids into proteins by the ribosomes

Question 54

What are nucleic acids?

Answer 54

huge organic molecules that contain carbon, hydrogen, oxygen, nitrogen, and phosphorus

Question 55

What are the basic units of nucleic acids?

Answer 55

Nucleotides, composed of a nitrogenous base, a pentose sugar, and a phosphate group

Question 56

What is ATP

Answer 56

Adenosine triphosphate: Temporary molecular storage of energy as it is being transferred from exergonic catabolic reactions to cellular activities

Question 57

What is hydrolysis of ATP?

Answer 57

The removal of terminal phosphate group by enzyme. Which release energy and leaves ADP ( adenosine diphosphate)