Basics Flashcards
1
Q
solids
A
- fixed shape/ volume
- can’t be compressed
- least KE
- regular arrangement
- vibrates in place
- strong intermolecular forces
2
Q
liquids
A
- no fixed shape
- takes shape of bottom of container
- flows
- can’t be compressed
- no regular arrangement
- moves randomly
3
Q
gases
A
- no fixed shape
- takes shape of whole container
- can be compressed
- no fixed volume
- weakest intermolecular forces
- no regular arrangement
- moves randomly quickly
4
Q
solid to liquid
A
melting
5
Q
liquid to gas
A
boiling/ evaporating
6
Q
gas to liquid
A
condensation
7
Q
liquid to solid
A
freezing
8
Q
kinetic particle theory
A
- more kinetic energy= weakest forces
- higher temp. = more kinetic energy
9
Q
pressure in gases decreases
A
volume increases
10
Q
concentration
A
measure of a number of particles in a given volume
11
Q
diffusion
A
net movement of particles from a region of high conc. to a region of low conc. down the conc. gradient
12
Q
concentration gradient
A
difference in conc. of a fluid between 2 areas
13
Q
greater molecular mass
A
particles move slower
14
Q
effect of temperature on rate of diffusion
A
- higher temp. = more kinetic energy = move faster = increases rate of diffusion
15
Q
element
A
substances made up of only one type of atom
16
Q
compound
A
elements chemically bonded together (not easily separated)
17
Q
mixture
A
substances found together, not chemically bonded (easily separated)
18
Q
electrical conductivity in metals
A
- good electrical conductors
(they have delocalised electrons and are free to carry the charge)
19
Q
thermal conductivity in metals
A
- good thermal conductors
20
Q
malleability in metals
A
- very malleable
(easy to shape and bend)
21
Q
ductility in metals
A
- very ductile
(easily stretched into wires)
22
Q
melting/ boiling point of metals
A
- high melting/ boiling points
23
Q
solvent
A
liquid in which a solute dissolves in
24
Q
solute
A
substance that is dissolved in a solvent
25
solution
mixture of (1 or more) solutes dissolved in a solvent
26
saturated solution
solution with maximum conc. of a solute dissolved
27
filtrate
liquid/ solution that passed through a filter
28
residue
substance that remains after evap./ distillation/ filtration
29
Rf formula
distance travelled by substance
-----------------------------------------------
distance travelled by solvent
30
mass number
larger number
31
proton number
smaller number
32
number of outershell electrons
group number
33
number of shells
period number
34
isotopes
atoms with the same proton number but different neutron number
35
group 7 (halogens)
- diatomic
- non-metals
- density increases going down
- melting point increases going down
- reactivity decreases going down
-iodine= grey-black solid
- bromine= red-brown liquid
- chlorine= yellow-green gas
36
transition elements
- high density
- high melting point
- unreactive
- catalysts
- forms coloured compounds
- ions with variable oxidation numbers
37
group 8 (noble gases)
- colourless gases
- monoatomic
- very unreactive (inert)
38
collision theory
- particles must collide with correct orientation and sufficient energy (activation energy)
39
activation energy
minimum energy needed to create a reaction
40
effect of catalysts in activation energy
lowers it
41
cations
positive ions
42
anions
negative ions
43
ionic bond
strong electrostatic attraction between oppositely charged ions
44
properties of ionic compounds
- high melting/ boiling point
- good conductor when aqueous/ molten
- poor conductor when solid
- giant ionic lattice
- regular arrangement of alternating positive and negative ions
45
properties of covalent bonds
- low melting/ boiling point
-poor electrical conductor
46
covalent bonds
pair of electrons is shared between 2 atoms leading to a noble gas electronic configuration
47
diamond
- giant covalent
- carbon atoms only
- each carbon bonded to 4 others
- no delocalised electrons
- can't conduct
- very hard, used for cutting tools
- high melting point
- doesn't dissolve in water
48
graphite
- only carbon
- each carbon boded to 3 other
- organised in hexagons, making layers
- conducts electricity
- layers can slide over eachother (soft and slippery) (weak forces between layers)
- used as lubricant and electrode
49
silicon (IV) dioxide (SiO2)
- silicon bonded with 4 oxygens, oxygen bonded with 2 silicons
- high melting point
- doesn't conduct
- doesn't dissolve
- hard
50
metals and dilute acid
make salt and hydrogen
51
metals and water
make metal hydroxide and hydrogen
52
metals and oxygen
makes metal oxides
53
aluminium properties
- very low density
- strong
- good conductor
- corrosion resistant
used to make:
- aircrafts (low den.)
- overhead electrical cables (low den.)(good cond.)
- food containers (corrosion resistant)
54
copper use
- electrical wiring (ductile/ elec. cond.)
55
reactivity series order
potassium
sodium
calcium
magnesium
aluminium
carbon
zinc
iron
hydrogen
copper
silver
gold
56
potassium and water
- violent
- potassium floats , melts, catches fire
- burns with lilac flame
- hydrogen gas released
57
sodium and water
- floats, moves rapidly
- heat melts it
- hydrogen gas released
58
calcium and water
- water becomes milky white
- hydrogen gas released
59
aluminium's unreactivity
- surface atoms react with oxygen in the air to form a protective aluminium oxide layer
- barrier to prevent inner metal from corroding
60
displacement reactions
- more reactive metal elements displace less reactive metal ions
- less reactive= reduced= gains electrons
- more reactive= oxidised= loses electrons
61
metallic bonding
electrostatic attraction between the positive metal ions in a giant metallic lattice and a sea of delocalised electrons
62
alloys
mixture of a metal with other elements
63
brass
mixture of copper and zinc
64
stainless steel
mixture of iron and chromium, nickel and carbon
used for cutlery (hard + resistant to rusting)
65
redox reactions
involving oxidation and reduction reactions and loss and gain of electrons and loss and gain of oxygen
66
oxidation
- gain of oxygen
- loss of electrons
- increase in oxidation number
67
reduction
- loss of oxygen
- gain of electrons
- decrease in oxidation number
68
oxidising agent
oxidises another substance and reduces itself
69
reducing agent
reduces another substance and oxidises itself
70
rusting
oxidation of iron
- conditions: air and moisture
iron + water + oxygen --> hydrated iron (iii) oxide
71
barrier methods
painting, coating with plastic, greasing, galvanising, sacrificial protection, greasing
72
sacrificial protection
- placing iron/ steel in contact with a more reactive metal (ie zinc)
73
galvanising
- coating iron/ steel with zinc
- barrier formed and if it is scratched, it is more reactive, so it corrodes instead of iron
