exam

Question 1

macro vs micro

Answer 1

big vs small

Question 2

empirical knowledge

Answer 2

observation

Question 3

theoretical knowledge

Answer 3

ideas to explain empirical knowledge

Question 4

atomic theory: greeks

Answer 4

matter can be divided into indivisible atoms

Question 5

atomic theory: democritus

Answer 5

atoms vary in size, constant motion, empty space around them

Question 6

atomic theory: aristotle

Answer 6

matter made of earth, air, wind, fire

Question 7

daltons atomic theory

Answer 7

• matter: indivisible atoms
• element atoms are identical
• law of constant proportion
• law of conservation of mass

Question 8

atomic theory: jj thompson

Answer 8

plum pudding model of electrons

Question 9

atomic theory: rutherford

Answer 9

alpha particles, nucleus, protons

Question 10

atomic theory: chadwick

Answer 10

confirmed neutrons

Question 11

atomic theory: bohr

Answer 11

electrons release light + orbit nucleus, planetary model

Question 12

radioisotopes: alpha

Answer 12

blocked by paper, 2+

Question 13

radioisotopes decay to emit

Answer 13

nuclear radiation + break apart easily

Question 14

radioisotopes: beta

Answer 14

blocked by aluminum, negative charge

Question 15

radioisotopes: gamma

Answer 15

penetrates most, no mass, speed of light

Question 16

nuclear reaction =

Answer 16

change in nucleus (presence of radioisotopes)

Question 17

metals: majority of

Answer 17

known elements

Question 18

non metals are

Answer 18

non conductors, brittle solids (or gases)

Question 19

metalloids are along the

Answer 19

staircase line, properties of metals and non metals

Question 20

group 1

Answer 20

alkali metals

Question 21

group 2

Answer 21

alkaline earth metals

Question 22

group 17

Answer 22

halogens

Question 23

group 18

Answer 23

noble gases

Question 24

groups 3-13

Answer 24

transition metals

Question 25

who published the first periodic law

Answer 25

mendeleev (properties = functions of atomic mass)

Question 26

atomic radius is the only trend to

Answer 26

decrease across a period and increase down a group (other than metallic properties)

Question 27

define ionization energy

Answer 27

energy required to remove an electron

Question 28

define electron affinity

Answer 28

energy released in gaining an electron

Question 29

define electronegativity

Answer 29

ability to attract electrons

Question 30

who proposed electronegativity

Answer 30

pauling

Question 31

ions are held together by

Answer 31

electrostatic forces

Question 32

lewis structure vs symbol

Answer 32

molecular vs ionic (sharing vs giving e)

Question 33

what if electronegativity is exactly 1.7

Answer 33

polar covalent

Question 34

if electronegativity is polar, it’s bc of

Answer 34

unequal sharing between dipoles

Question 35

define polarity

Answer 35

distribution of electrical charge over bonded atoms

Question 36

geometric molecule =

Answer 36

non polar

Question 37

molecule can have polar covalent bonds but be non polar if

Answer 37

not symmetrical

Question 38

define intermolecular forces

Answer 38

between molecules

Question 39

types of intermolecular forces

Answer 39

- van der waals - dipole dipole - london dispersion - hydrogen bonding

Question 40

hydrogen bonds are stronger than

Answer 40

dipole dipole

Question 41

define intramolecular forces

Answer 41

within single molecules (ionic or covalent bonds)

Question 42

there are no intermolecular forces in

Answer 42

ionic compounds

Question 43

hydrogen bonds: hydrogen must be bonded to

Answer 43

N, O, F (highly electronegative)

Question 44

water has unusually

Answer 44

- high melting boiling points - low density - high surface tension - high specific heat capacity

Question 45

evidence of chemical reaction

Answer 45

- colour change - energy is released/absorbed (sparks) - gas produced - precipitate

Question 46

law of conservation of mass

Answer 46

reactants mass = products mass

Question 47

catalyst:

Answer 47

speeds up a reaction

Question 48

acid + sulfate

Answer 48

H2S + salt

Question 49

acid + carbonate

Answer 49

water + CO2 + salt

Question 50

acid + sulfite

Answer 50

water, SO2, salt

Question 51

metal oxanion —>

Answer 51

ionic compound and gas

Question 52

metal carbonate —>

Answer 52

metal oxide and carbon dioxide

Question 53

N A

Answer 53

avogadros constant

Question 54

avogadros constant is the number of atoms in

Answer 54

12 g of carbon-12

Question 55

why could it not yield 100%

Answer 55

- competing reverse reaction - measurements/spills/purifications - impurities - side reactions

Question 56

air and water are usually

Answer 56

excess reagents

Question 57

why is it important to use LR

Answer 57

- saves money and resources - environment (less resources) - uses undesired - improves efficiency

Question 58

transparent gases and liquids are

Answer 58

solutions (entities too small to block light)

Question 59

translucent: opaque gases or liquids:

Answer 59

heterogenous (entities block light, like blood)

Question 60

ionic compounds dissolve in

Answer 60

water

Question 61

like dissolves like:

Answer 61

polar and polar, non polar and non polar

Question 62

charles law

Answer 62

v/t gas volume is proportional to its temperature in kelvins

Question 63

boyles law

Answer 63

pv gas volume is inversely proportional to pressure

Question 64

gay lussacs law

Answer 64

pt gas pressure is directly proportional to temperature

Question 65

combined gas law

Answer 65

pv/t product of pressure and volume divided by temperature is constant