St Edmund's Girls' School
Q1.
The diagrams show five different atoms, A, B, C, D and E.
(a)
Which atom, A, B, C, D or E:
(i) has an atomic number (proton number) of 3
Atom
(1)
Atom
(ii) has a mass number of 2
(1)
Atom
(iii) is in Group 2 of the periodic table?
(1)
(b)
Atom
Which two atoms from A, B, C, D and E are isotopes of the same element?
and Atom
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St Edmund's Girls' School
(1)
(c)
Which particle in an atom has a negative charge? .......................................
(1)
(Total 5 marks)
Q2.
Pure carbon can exist in two forms, diamond and graphite.
(a)
Complete the diagram to show the electronic structure of a carbon atom.
A carbon atom has 6 electrons.
Show the electrons as crosses (x).
(1)
(b)
A drill bit is used to cut holes through materials. The cutting end of this drill bit is
covered with very small diamonds.
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By Wanderlinse [CC By 2.0], via
Flickr
(i)
What property of diamond makes it suitable for use on the cutting end of a
drill bit?
...............................................................................................................
(1)
(ii)
Explain, as fully as you can, why diamond has this property. Use your
knowledge of the structure and bonding of diamond and the information shown
opposite to help you to answer this question.
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(3)
(c)
Explain why graphite is a good conductor of electricity and why diamond does not
conduct electricity.
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St Edmund's Girls' School
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(3)
(Total 8 marks)
Q3.This question is about atoms and molecules.
(a)
Complete the table to show the relative masses of the particles in atoms.
Name of particle
Relative mass
Proton
...........................
Neutron
1
Electron
...........................
(2)
(b)
The diagram shows an oxygen atom.
Use the correct number to complete each sentence.
8
16
18
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St Edmund's Girls' School
The atomic (proton) number of the oxygen atom shown above is ............................. .
The mass number of the oxygen atom shown above is ............................................. .
(2)
(c)
(i)
Draw a ring around the correct answer to complete each sentence.
isotopes.
Oxygen atoms with different numbers of neutrons are called molecules.
polymers.
(1)
(ii)
An oxygen atom with a different number of neutrons has 10 neutrons.
Draw a ring around the symbol which represents this atom.
(1)
(d)
A water molecule contains hydrogen and oxygen atoms.
(i)
Use the correct answer to complete the sentence.
a compound
an element
a mixture
Water is ..................................................................... .
(1)
(ii)
Draw a ring around the correct structure of a water molecule.
H–O–H
O–H–H
O–H–O
(1)
(iii)
Draw a ring around the type of bonding in a water molecule.
covalent
ionic
metallic
(1)
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(iv)
Draw a ring around the correct answer to complete each sentence.
gaining
The bonds in a water molecule are formed by losing
electrons.
sharing
(1)
(Total 10 marks)
Q4.The diagram shows a small part of the structure of silicon dioxide.
(a)
Use the diagram above to answer the question.
Draw a ring around the correct answer to complete each sentence.
two
In silicon dioxide, each silicon atom is bonded with
three oxygen atoms.
four
ionic.
The bonds in silicon dioxide are
covalent.
metallic.
(2)
(b)
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St Edmund's Girls' School
© Oleksiy Mark/iStock
Silicon dioxide is used as the inside layer of furnaces.
Suggest why.
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........................................................................................................................
(1)
(c)
Nanowires can be made from silicon dioxide.
Draw a ring around the correct answer to complete the sentence.
brittle.
The word ‘nano’ means the wires are very
thick.
thin.
(1)
(Total 4 marks)
Q5.The following steps show how to use a type of glue.
Step 1 Measure out equal amounts of the liquids from tubes A and B.
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St Edmund's Girls' School
Step 2 Mix the liquids to make the glue.
Put a thin layer of the glue onto each of the surfaces to be joined.
Step 3 Put the pieces together and hold them with tape.
Step 4 Leave the glue to set.
(a)
When liquids A and B are mixed a chemical reaction takes place.
This reaction is exothermic.
What does exothermic mean?
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(2)
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(b)
The time taken for the glue to set at different temperatures is given in the table
below.
(i)
Temperature in°C
Time taken for the glue to set
20
3 days
60
6 hours
90
1 hour
Use the correct answer from the box to complete each sentence.
decreases
increases
stays the same
When the temperature is increased the time taken for the glue to set
...............................................................................................................
When the temperature is increased the rate of the setting reaction
...............................................................................................................
(2)
(ii)
Tick ( ) two reasons why an increase in temperature affects the rate of
reaction.
Reason
Tick (
)
It gives the particles more energy
It increases the concentration of the particles
It increases the surface area of the particles
It makes the particles move faster
(2)
(Total 6 marks)
Q6.
(a)
The symbol equation for the decomposition of hydrogen peroxide is:
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St Edmund's Girls' School
2H2O2
→
2H2O + O2
Complete the word equation for the decomposition of hydrogen peroxide.
Hydrogen peroxide
→ ....................................
+ ....................................
(1)
(b)
A student did an experiment to see how quickly hydrogen peroxide decomposes.
The student used the apparatus shown below to measure the volume of oxygen.
(i)
Draw a straight line of best fit to complete the graph.
(1)
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St Edmund's Girls' School
(ii)
Draw a circle around the anomalous point on the graph.
(1)
(iii)
What is the volume of oxygen given off after 15 seconds?
......................... cm3
(1)
(iv)
How did the volume of oxygen change between 0 and 25 seconds?
...............................................................................................................
(1)
(c)
The student wanted to make the reaction faster.
Draw a ring around the correct answer to complete each sentence.
higher.
(i) To make the reaction faster, the temperature should be
lower.
the same.
(1)
more dilute.
(ii)
To make the reaction faster, the hydrogen peroxide should be
more
concentrated.
the same.
(1)
(d)
The diagram represents the bonding in oxygen.
O=O
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Draw a ring around the correct answer to complete each sentence.
share
(i) When two oxygen atoms bond, the atoms
transfer
electrons.
delocalise
(1)
ionic
(ii)
The oxygen atoms are joined by
metallic bonds.
covalent
(1)
simple molecules.
(iii)
Oxygen is made of
a giant lattice.
macromolecules.
(1)
(e)
When hydrogen peroxide decomposes water is produced.
Which two statements in the table explain why water is a liquid at room
temperature?
Tick (
) the two statements.
Statement
Tick (
Water has a boiling point of 100 °C.
Water is made of ions.
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St Edmund's Girls' School
Water has a melting point lower than room
temperature.
Water has a giant covalent structure.
(2)
(Total 12 marks)
Q7.(a)
Some students did an experiment to find the temperature change when hydrochloric acid
reacts with sodium hydrogencarbonate.
The results are in the table.
Number of spatula
Start temperature
Final
Change in
measures of sodium
in °C
temperature in °C temperature in °C
hydrogencarbonate
(i)
2
20
16
4
4
20
14
6
6
19
11
8
8
20
10
10
10
19
9
10
12
20
10
10
Describe, as fully as you can, the trends shown in the students’ results.
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(3)
(ii)
State the type of energy transfer for this reaction.
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(1)
(b)
Sodium hydrogencarbonate is used as baking powder for making cakes.
When the cake mixture is baked the sodium hydrogencarbonate decomposes.
The equation for the reaction is:
(i)
The cake mixture rises when baked.
© Michael Valdez/iStock
Use the equation to suggest why.
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St Edmund's Girls' School
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(1)
(ii)
The same reaction can be reversed to produce sodium hydrogencarbonate
from sodium carbonate.
Na2CO3
+
H2O
+ CO2
2NaHC
O3
Do the reactants need to be heated?
Give a reason for your answer.
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(1)
(c)
(i)
Calculate the relative formula mass of sodium hydrogencarbonate (NaHCO3).
Relative atomic masses (Ar): H=1; C=12; O=16; Na=23
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Relative formula mass (Mr) = ............................................
(2)
(ii)
Calculate the percentage by mass of carbon in sodium hydrogencarbonate.
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Percentage of carbon = .................................................. %
(1)
(Total 9 marks)
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St Edmund's Girls' School
M1.
(a)
(i)
B
1
(ii)
A
1
(iii)
C
1
(b)
D and E
1
(c)
electron
1
[5]
M2.
(a)
2,4 (drawn as crosses) on shells
accept dots / e / - etc.
1
(b)
(i)
hard
allow rigid / high melting point
do not allow references to bonding
ignore strong
ignore unreactive
ignore structure
1
(ii)
any three from
max 2 if ionic / metallic / molecule / intermolecular bonds or
incorrect number of bonds
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St Edmund's Girls' School
•
giant structure / lattice / macromolecular
allow many bonds
•
covalent (bonds)
•
(covalent) bonds are strong
accept needs lots of energy to break bonds (owtte)
•
(each) carbon / atom forms four bonds
or
(each) carbon / atom bonded to four other atoms
3
(c)
any three from:
max 2 if ionic / ions / metallic / molecule
‘it’ needs to be qualified
graphite
•
has delocalised / free electrons
do not accept the electrons move unless qualified (around
structure etc)
or
electrons that can move through / around the structure
•
each carbon is joined to three other carbon atoms
allow graphite has three bonds
or
one electron from each atom is free / delocalised
diamond
•
has no free / delocalised electrons
do not accept the electrons do not move
or
no electrons that move around the structure
•
all the electrons are used for bonding
allow diamond has 4 bonds
or
each carbon joined to four other carbon atoms
3
[8]
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St Edmund's Girls' School
M3.(a)
proton 1
ignore ±
1
electron very small owtte
allow zero
allow values from 1 / 1800 to 1 / 2000 or 0.0005 – 0.00055
1
(b)
8
1
16
1
(c)
(i)
Isotopes
1
(ii)
1
(d)
(i)
compound
1
(ii)
H-O-H
1
(iii)
covalent
1
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(iv)
sharing
1
[10]
M4.(a)
four
1
covalent
1
(b)
because it has a high melting point
accept it won’t melt
accept it won’t decompose or react
allow withstand high temperatures
ignore boiling point
1
(c)
thin
1
[4]
M5.(a)
heat / energy
1
given out / transfers to surroundings
the mark for given out / transfers to cannot be awarded
without heat / energy
allow given off
1
(b)
(i)
decreases
1
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increases
1
(ii)
it gives the particles more energy
1
it makes the particles move faster
1
[6]
M6.
(a)
oxygen and water
both needed for mark
allow hydrogen oxide for water
in any order
ignore formulae
1
(b)
(i)
best fit line, omitting point at 10s
straight line drawn through all correct points
1
(ii)
circle around point at 10 s
allow any indication
1
(iii)
7.5
allow ecf from candidate’s line
1
(iv)
increases (with time)
accept goes from 0 to 12.5
1
(c)
(i)
higher
1
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(ii)
more concentrated
1
(d)
(i)
share
1
(ii)
covalent
1
(iii)
simple molecules
1
(e)
Water has a boiling point of 100°C
1
Water has a melting point lower than room temperature
1
[12]
M7.(a)
(i)
the more sodium hydrogencarbonate the greater the temperature change
accept examples from the table
1
up to 8 spatula measures
accept any correct indication of when change occurs
1
then the temperature change is constant
if no marks awarded allow 1 mark for:
the more sodium hydrogencarbonate the lower the final
temperature
1
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(ii)
energy is taken in from the surroundings or endothermic
1
(b)
(i)
gas / carbon dioxide / steam / water is produced
accept carbon dioxide is a gas or steam / water is a gas
allow gas / air expands when heated
1
(ii)
no, because (reaction) is exothermicoryes, to start the reaction
allow no, because (reactants) were formed by heating
ignore references to cooling
1
(c)
(i)
84
correct answer with or without working gains 2 marks
if no answer or incorrect answer then evidence of 23 +1 + 12
+ (3 × 16) gains 1 mark
2
(ii)
14.29
accept rounding to 14.3 or 14
allow ecf from (c)(i)
1
[9]
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