Chapter 2 Atoms, Melocules And Water

Question 1

______________ makes up the nucleus of am atom

Answer 1

Proton and neutrons

Question 2

Living organisms are composed of which atoms?

Answer 2

Carbon, nitrogen, oxygen and hydrogen

Question 3

The ability of an atom to attract electrons in a bond with another atom is termed its

Answer 3

Electro negativity

Question 4

Hydrogen bonds differ from covalent a bonds in that

Answer 4

Covalent so bond involve sharing of electrons between atoms, but hydrogen bonds are the result of weak attractions between a hydrogen atom of a polar molecule and an electronegative atom of another polar bond

Question 5

A free radical

Answer 5

Is an atom with one unpaired electron in its outer shell and can cause considerable cellular damage

Question 6

Chemical reactions in living organisms

Answer 6

Requires energy to begin/usually requires a catalyst to speed up the process/are usually reversible/occurred in liquid environment such as water

Question 7

So lutes that easily dissolve in water are said to be

Answer 7

Hydrophilic and polar molecules

Question 8

The sum of the atomic masses of all atoms of a molecule is its

Answer 8

Molecular mass

Question 9

Reactions in which water is used to break apart other molecules are known as _______ reactions

Answer 9

Hydrolysis

Question 10

Atoms

Answer 10

The smallest functional units of matter

Can form into chemical elements and cannot be further broken down

Question 11

Covalent bonds

Answer 11

Atoms share a pair of electrons, can occur between atoms whose outer shells are not full
Strong bonds
Atoms tend to be more Stable when outer shell is filled with electrons

Question 12

Electronegativity

Answer 12

Measure of its ability to attract electrons in a bond with another atom

Question 13

Polar covalent bonds

Answer 13

A covalent bond between two atoms that have different electronegativities; the shared electrons are closer to the atom of higher electronegativity than the atom with lower electronegativity.

Question 14

Polar molecules

Answer 14

A molecule continuing significant numbers of polar bonds

Question 15

Non polar covalent bond

Answer 15

A strong bond formed between two atoms of similar electronegativities in which electrons are shared between the atoms

Question 16

Cations

Answer 16

I answered have a net positive charge

Question 17

Anions

Answer 17

Ions with a net negative charge

Question 18

Ionic bond

Answer 18

Occurs when a cation binds to an anion

Na+ and Cl- forms NaCl table salt

Question 19

Ions

Answer 19

Formed when an atom gains or loses electrons

Question 20

Chemical reaction

Answer 20

Occurs when one or more substances are changed into other substances by making or breaking of chemical bonds

Question 21

Hydrophilic

Answer 21

Water loving

Molecules that contain and ionic and/or polar covalent bonds dissolve in water

Question 22

Hydrophobic

Answer 22

Water fearing

Question 23

Amphipathic

Answer 23

Both loves

May to into spheres called micelles

Question 24

Protons

Answer 24

Positive, found a nucleus, same number as electrons

Question 25

Neutrons

Answer 25

Neutral, found a nucleus, number can vary

Question 26

Electrons

Answer 26

Negative, found in the orbitals, same number as protons

Question 27

Rutherford’s experiment

Answer 27

Hypothesized that atoms in a thin sheet of gold foil would be composed of diffuse, evenly distributed positive charges that would cause alpha particles to be slightly deflected as they pass through

Question 28

Rutherford’s results

Answer 28

98% were undeflected
<2% were slightly deflected
0.01% bounced back
Conclusion: most of the volume of an atom is empty space, with the positive charges concentrated in small volume

Question 29

Most of the mass of an atom is found in the

Answer 29

Nucleus

Question 30

Diameter of atom

Answer 30

100,000 times the diameter of atomic nucleus

Question 31

Orbitals

Answer 31

Areas in which the probability of finding an electron is high
S orbitals - spherical
P orbitals - propeller

Question 32

Potential energy

Answer 32

Is the energy that matter possesses because of its location or structure

Question 33

Energy

Answer 33

Is defined as the capacity to cause change

Question 34

Moles

1 mole of any element contains

Answer 34

6.022x10^23

Question 35

Isotopes

Answer 35

Multiple forms of an element that differ in the number of neutrons

Question 36

Radioisotopes

Answer 36

Unstable isotopes found in nature
Lose energy through radiation
Emit subatomic particles

Question 37

32P has an atomic number of 15. How many neutrons does 32P have?

Answer 37

17

Question 38

Nitrogen is more electronegative than hydrogen. In ammonia (NH3), nitrogen is joined to three hydrogen atoms by covalent bonds. The nitrogen atom tajes on a _____________ charge

Answer 38

Positive

Question 39

Heat of vaporization

Answer 39

Heat required to vaporize 1 mole of any substance at its boiling point under standard pressure

Question 40

Heat of fusion

Answer 40

Heat that must be released from substance to cause a change from a liquid to a solid state

Question 41

Specific heat

Answer 41

Keep required per unit of mass to raise the temperature of that mass by 1°C

Question 42

Solutes

Answer 42

Substances dissolved in a liquid

Question 43

Solvent

Answer 43

Liquid in which they are dissolved

Question 44

Solution

Answer 44

Solutes dissolved in a solvent

Question 45

Acids

Answer 45

I molecules that release hydrogen ions in solution

Question 46

Base

Answer 46

I’m OK with that lowers a hydrogen plus concentration

Question 47

Which of the following has the highest concentration of hydrogen plus ions a. pH 2 b. pH 6 c. Ph8 d. ph 14

Answer 47

PH two

Question 48

Dehydration

Answer 48

Removal of a water molecule to form a covalent bond between two modules

Question 49

Evaporation

Answer 49

How to animals this a paid body heat by removing heat from skin and respiratory tract

Question 50

Cohesion

Answer 50

Between water molecules aids in movement through vessels of plants

Question 51

Adhesion

Answer 51

Between water molecules and other surfaces allows it to line surfaces and act as a lubricant in digestive tracts, between bones, etc

Question 52

Which of the following has the highest concentration of hydrogen plus ions a. pH 2 b. pH 6 c. Ph8 d. ph 14

Answer 52

PH two

Question 53

Dehydration

Answer 53

Removal of a water molecule to form a covalent bond between two modules

Question 54

Evaporation

Answer 54

How to animals this a paid body heat by removing heat from skin and respiratory tract

Question 55

Cohesion

Answer 55

Between water molecules aids in movement through vessels of plants

Question 56

Adhesion

Answer 56

Between water molecules and other surfaces allows it to line surfaces and act as a lubricant in digestive tracts, between bones, etc