1 Flashcards
1
Q
Best way for filtration
James Chadwick proved the existence of the
Mass number of copper
A
Funnel
Neutron
63
2
Q
In simple distillation, the mixture is heated to make the liquid
A
evaporate
3
Q
Bromine is in Group?
A
7
4
Q
What is the structure of hydrogen bromide?
A
small molecule
5
Q
Explain how the reactivity of the halogens changes going down Group 7.
A
the reactivity decreases (going down Group 7)
6
Q
The two types of particle in the centre of the atom are the proton and the
A
Neutron
7
Q
Niels Bohr suggested particles orbit the centre of the atom. This type of particle is the
A
Electron
8
Q
The two types of particle with the same mass are the neutron and the
A
Proton
9
Q
What do the dots and crosses represent in the diagram
A
Electrons
10
Q
formula for the molecule of ammonia
A
NH3
11
Q
Ammonia manufactured by?
A
Haber process
12
Q
>
A
reversible (reaction) / reaction can go both ways
13
Q
Produces ammonium nitrate
A
Ammonia reacts with nitric acid
14
Q
Nitrate need
A
Nitric acid
15
Q
why farmers spread ammonium nitrate on their fields.
A
as a fertiliser (1) • contains (a high percentage of) nitrogen (1) • help promote plant growth / increases crop yield (1)
16
Q
pic pipette
A
apple
17
Q
pic conical flask
A
flats
18
Q
Describe how the pipette should be used to measure exactly 25.00 cm3 of sodium hydroxide solution into the conical flask.
A
use a pipette filler (1) • wash pipette with sodium hydroxide solution (1) • draw the liquid up so (the bottom of the meniscus) touches the line (1)
19
Q
pic burette
A
hairdressers
20
Q
Titration
A
determine the concentration of an identified analyte
21
Q
Give a reason why universal indicator is not a suitable indicator to use in an acid-alkali titration.
A
it does not show sharp colour change at end point / not known which colour change gives correct end point
22
Q
relative mass of a proton?
A
1
23
Q
Argon group
A
0
24
Q
Period
A
Row
25
empirical formula of butene
CH2
26
Test for CO2
(bubble gas through) limewater (1)
• (limewater) turns {milky / cloudy / white precipitate} (1)
27
Fire symbol
Flammable
28
Elements in barium sulfide
Barium sulfur
29
Safety when toxic substance
wear gloves (1) • {so does not contact/to protect your} skin (1) OR • wear goggles (1) • {so does not contact/to protect} the eyes (1) OR • use in fume cupboard / mask (1) • so you do not inhale it (1)
30
condenser is used.
to cool (1)
• so (water) {vapour/gas} turns to liquid (1)
31
pic Bunsen burner.
School side
32
Explain why these changes are called physical changes rather than chemical changes.
physical changes do not result in formation of a new substance / chemical change results in formation of a new substance (1)
• physical change is easily reversed / chemical change is not easily reversed (1)
33
Solid to liquid
Melting
34
Liquid gas
Evaporation
35
Explain how alloying changes these pure metals to make the alloys more suitable for the given uses.
(
an alloy is a mixture of metals • because larger/different sized atoms introduced in alloying, • stop layers moving easily over one another • therefore individual alloy is stronger/harder • an aluminium alloy is magnalium • pure aluminium is not suitable for making aircraft as it bends too easily / too weak • aluminium alloy stronger • magnesium atoms lighter than aluminium atoms, • therefore alloy still low density / lower density than aluminum alone • an iron alloy is stainless steel • pure iron is not suitable for cutlery as it bends too easily / too weak • iron corrodes, • corrosion would contaminate food • stainless steel does not corrode • gold alloy harder • therefore more hard wearing • gold alloys less likely to change shape when worn • alloying can change the colour of the gold
36
what is meant by oxidation.
gain of oxygen lose electrons
37
Explain why painting iron objects prevents corrosion.
the paint {excludes/acts as a barrier/protective layer/shield} (1)
• (excludes) air / oxygen / water (1)
38
Protect iron corrosion
Sacrificial protection
39
State two characteristic properties of metals
• high melting points (1) • high boiling points (1) • malleable (1) • conduct electricity (1) • conduct heat (1) • high density (1) • shiny (1) • ductile (1) • strong (1) • sonorous (1)
40
acid used to make chlorides.
Hydrochloric acid
41
make salts
Acids
42
Explain structure changes nickel atom, Ni, changes when it forms a nickel ion, Ni2
loss of electron(s) (1)
• two electrons (1)
43
Iron ore contains
iron oxide.
44
thermometer measures
Temperature
45
polystyrene cup pic
Alsatger town
46
exothermic heat
release of heat
47
Best way to measure liquid
measuring cylinder
48
a yellow flame
Sodium
49
the limewater goes milky what gas
CO2
50
Inner pack solid with pack of water in it.
| Explain why the pack goes cold. when burst
the solid {dissolves/ reacts with the water} (1)
• {takes in /absorbs} heat / is endothermic (1)
51
Why the pack can be used only once.
reaction) irreversible
52
Line of best fit
Straight line through most
53
Hydrogen peroxide decomposes to form
water and oxygen.
54
gas) syringe pic
Keats walk
55
atom has a radius of about
0.1 nm.
56
A useful property of nanoparticles in sunscreens is that they
prevent harmful UV radiation reaching the skin
57
Nanoparticle surface area of 38 400 nm2 and a volume of 51 200 nm3. Calculate the surface area to volume ratio.
allow 2 for correct answer with or without working
51200 (1) 38400 1 : 1.33 (1)
58
State why ethane is described as a hydrocarbon.
contains carbon and hydrogen (atoms) (1) only (1)
59
Draw a molecule of ethane showing all covalent bonds.
CC H's around
60
crude oil is a
finite resource
61
The substances ethane, C2H6, octane, C8H18, and pentadecane, C15H32, are all found in crude oil. These substances
are in the same homologous series
62
Crude oil passed of to the column it is
Heated
63
transition metal? density
High
64
transition metal? catalyst?
YES
65
transition metal? colour
Coloured
66
Lubricating bike chain prevents corrosion of the steel chain.
air/oxygen} excluded / {water/moisture} excluded / oil acts as a barrier (1)
• {air/oxygen} and {water/moisture/damp conditions} both needed (for iron to rust / corrosion) (1)
67
Iron fences can be galvanised by coating them with a layer of zinc. When the layer of zinc is scratched exposing the iron to the weather, the iron does not rust. Explain why the exposed iron does not rust.
zinc corrodes {easier than / in preference to / OWTTE} iron / zinc reacts with air and water instead (1)
• zinc is more reactive than iron / zinc is sacrificial / zinc has a higher tendency to form ions (1)
68
Metals have high melting points. Explain, in terms of their structure and bonding, why metals have high melting points.
metal ions / cations} surrounded by (delocalised) electrons (1)
* strong {forces of attraction / bonding} (between (delocalised) electrons and {metal ions / cations}) (1)
* needs lots of energy to {separate the particles / break bonds / break forces of attraction} (1)
69
Describe the test to show the gas is hydrogen.
apply lighted splint (1)
• (squeaky) pop (1)
70
Explain how the structure of a nickel atom, Ni, changes when it forms a nickel ion, Ni2+.
* loss of electron(s) (1)
| * two electrons (1)
71
Aluminium cannot be extracted by heating its oxide with carbon. Aluminium has to be extracted from its oxide by electrolysis. Explain why.
aluminium is high in reactivity / aluminium oxide is (very) stable (1)
• aluminium (oxide) cannot be reduced by carbon (1)
72
Describe how growing plants can result in the phytoextraction of copper
plants absorb {copper/metal} (ions) from the {soil/ores} / plants concentrate copper ions (1)
• plants (harvested and) burned (to leave copper/metal compound) (1)
73
Hydrogen burns in
air
74
Boiling point of water
100d
75
Boiling point of hydrogen
-253d
76
Lead can be obtained by heating its oxide with
Carbon
77
In most reactions, the percentage yield of any product is less than 100%. Give two reasons why the percentage yield is less than 100%.
(
incomplete / reversible reactions
* competing/unwanted/side reactions
* practical losses during the experiment / loss on transfer from one piece of equipment to another
78
Molten zinc chloride is an
electrolyte.
79
Covalent substances can be
simple molecular covalent or giant covalent.
80
Ammonia, NH3, is made by reacting nitrogen with hydrogen. Write the balanced equation for this reaction.
N2 + 3H2 → 2NH3 (2)
left hand side formulae (1) balancing of correct formulae (1)
81
Why should the student use a pencil and not a pen to draw the start line? Chromatography
Smudge
82
Water level …. the line
Below
83
The mixture of compounds in gas chromatography is
separated
84
Give one advantage of using instrumental methods of analysis.
accurate • sensitive • rapid / fast • small sample
85
Which of these values could be the pH of sulfuric acid?
| 1, 7, 14, 8
1
86
Funnel drawn
y
87
What type of bonding holds the atoms together in oxygen?
covalent
88
Oxygen boiling point
Low
89
Oxygen consists of
Small molecules
