Chapter 2 Notes

Question 1

chemistry

Answer 1

Study of the nature of matter

Question 2

matter

Answer 2

anything that occupies space and has mass (include solids liquids and gases in our bodies as well as surroundings)

Question 3

all things are composed of

Answer 3

elements

Question 4

elements

Answer 4

Basic chemical substances that make up matter

Question 5

20 elements

Answer 5

needed by living things

Question 6

which for atoms make up 95% of the human body

Answer 6

carbon, oxygen, hydrogen, nitrogen

Question 7

atoms

Answer 7

tiny particles which make up elements

Question 8

nucleus

Answer 8

Central portion, positive

Question 9

parts of the atom

Answer 9

nucleus, electrons around the nucleus

Question 10

charge of the atom

Answer 10

neutral

Question 11

nucleus contains

Answer 11

protons, positively charged particles-neutrons, uncharged particles

Question 12

where are electrons found

Answer 12

found in a cloud outside the nucleus

Question 13

characteristics of electrons

Answer 13

very small, have a negative charge

Question 14

atomic number

Answer 14

equal to the number of protons in its nucleus

Question 15

atomic weight

Answer 15

average of the relative wait (mass numbers) of all the isotopes of an element, neutrons and protons

Question 16

bonding of atoms

Answer 16

when atoms combine with each other, they gain or lose electrons, or share electrons with other atoms

Question 17

electrons arranged in

Answer 17

shelves

Question 18

first shell

Answer 18

two electrons

Question 19

Second shell

Answer 19

eight electrons

Question 20

third shell

Answer 20

eight or 18 electrons

Question 21

ion

Answer 21

particle that gains or loses electrons

Question 22

atoms that lose electrons become ______ charged

Answer 22

positively

Question 23

negatively charged

Answer 23

atom that gains electrons

Question 24

ions

Answer 24

atom with a positive or negative electric charge

Question 25

ionic bond

Answer 25

atoms that bond by transferring electrons

Question 26

covalent bond

Answer 26

Chemical bond created by electron sharing between atoms

Question 27

hydrogen bond

Answer 27

when a hydrogen atom that is already covalently link to the electronegative atom is attacked by another nitrogen or oxygen atom and a bridge is formed between them

Question 28

molecule

Answer 28

combination of two or more atoms held together by a chemical bond to form a new particle

Question 29

compound

Answer 29

when two or more different kinds of atoms bond to form a new substance

Question 30

molecular formula

Answer 30

represent the number and kinds of atoms in a molecule

Question 31

h2o

Answer 31

2 atoms h 1 atom o

Question 32

c6h12o6

Answer 32

6 atoms c 12 atoms h 6 atoms o

Question 33

synthesis

Answer 33

when reactants combine to form a larger more complex molecule a+b->ab

Question 34

decomposition

Answer 34

when a molecule is broken down into smaller molecules or its constituent atoms ab-> a+b

Question 35

exchange

Answer 35

parts of the reactant exchange partners, producing different product molecules ab+cd=ad+cb

Question 36

reversible

Answer 36

if chemical bonds are made, they can be broken (all chemical reactions) a+b ab

Question 37

electrolytes

Answer 37

substances that release ions in water

Question 38

acids

Answer 38

electrolyte that releases hydrogen (h+) ions in water | hcl-> h++cl-

Question 39

bases

Answer 39

electrolytes that release ions that combine with hydrogen ions naoh->na + + oh

Question 40

1-6

Answer 40

acid

Question 41

8-14

Answer 41

base

Question 42

ph

Answer 42

relative concentration of hydrogen ions in various bodily fluids (concentrated units used to measure)

Question 43

ph scale

Answer 43

0 to 14

Question 44

7

Answer 44

neutral. contains equal hydroxyl (oh-) and hydrogen (h+) ions

Question 45

acidic

Answer 45

contains more hydrogen ions than hydroxyl ions | less than 7

Question 46

basic

Answer 46

alkaline contains fewer hydrogen ions than hydroxyl atoms ph above 7

Question 47

ph

Answer 47

values of importance

Question 48

2.0

Answer 48

gastric juices (very acidic)

Question 49

7.4 blood

Answer 49

almost neutral.

Question 50

how does stomach not burn up

Answer 50

``` secrets mucus (base) if not ulcer ```

Question 51

what happens if ph of blood gets too low

Answer 51

things passing through dissolved

Question 52

what happens if ph changes

Answer 52

affects metabolism and homeostasis

Question 53

inorganic

Answer 53

molecules that lack carbon

Question 54

why are inorganic molecules called electrolytes

Answer 54

dissolve in water

Question 55

4 common inorganic substances

Answer 55

water, oxygen, carbon dioxide, inorganic salts

Question 56

water

Answer 56

most abundant compound in body

Question 57

makes up 2/3 of the body's weight

Answer 57

water

Question 58

water is a major component of

Answer 58

blood layers

Question 59

how are chemicals transported within the body

Answer 59

water

Question 60

water absorbs

Answer 60

and transports nutrients