Q1. A limestone quarry is in an area of natural beauty and near several villages. The company operating the quarry wants planning permission to build a new cement works in the quarry. The diagram shows some of the substances used and produced at a cement works. (a) Limestone is mainly calcium carbonate, CaCO 3 . Write the correct number in the box to complete each sentence. (i) The formula shows that calcium carbonate, CaCO 3 , contains different elements. (1) (ii) Calcium carbonate, CaCO 3 , contains a total number of atoms. (1) (b) The company wants the new cement works because the nearest cement works is 100 km from the quarry. The company argues that a new cement works sited inside the quarry would reduce carbon dioxide emissions. Suggest why the new cement works might reduce carbon dioxide emissions. ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... (1) Page 1 of 31
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(1)‚¬€€€€€€€€ Limestone contains calcium carbonate. (a)€€€€ Calcium carbonate has the formula CaCO 3. Complete the sentence by writing in the correct numbers.
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Q1. A limestone quarry is in an area of natural beauty and near several villages. The company operating the quarry wants planning permission to build a new cement works in the quarry.
The diagram shows some of the substances used and produced at a cement works.
(a) Limestone is mainly calcium carbonate, CaCO3.
Write the correct number in the box to complete each sentence.
(i) The formula shows that calcium carbonate, CaCO3,
contains different elements. (1)
(ii) Calcium carbonate, CaCO3, contains a total number of atoms.
(1)
(b) The company wants the new cement works because the nearest cement works is 100 km from the quarry. The company argues that a new cement works sited inside the quarry would reduce carbon dioxide emissions.
Suggest why the new cement works might reduce carbon dioxide emissions.
(ii) In the kiln the raw materials are heated to about 1500°C. The limestone (calcium carbonate) is broken down at this temperature. Complete the word equation for this reaction.
Draw a ring around the correct gas in the box to complete the sentence.
(1)
The gas formed when calcium carbonate decomposes is
argon.
carbon dioxide.
nitrogen.
(c) The cement works starts to burn a different fuel.
Local residents are concerned because more children are suffering asthma attacks. Residents have also noticed that parked cars are becoming dirty because of smoke particles from the chimney.
The table shows the possible medical risk from smoke particles.
Particle size in mm Medical effect
Larger than 0.4 No medical risks known
0.3 and smaller Causes asthma attacks
0.2 and smaller May cause cancer
(i) Give two reasons why local residents are concerned about the cement works burning a different fuel.
(d) (i) Quicklime (calcium oxide) can be converted to slaked lime (calcium hydroxide) by adding water. Write a word equation to represent this reaction.
(c) The cement works continue to burn the different fuel.
Local residents are concerned because more children are suffering asthma attacks. Residents have also noticed that parked cars are becoming dirty because of smoke particles from the chimney.
The table shows the possible medical risk from smoke particles.
It is also recommended that to avoid damage to health, the concentration of any particles should be no higher than 2 parts per million (ppm).
Scientists were brought in to monitor the emissions from the cement work’s chimney. They positioned four sensors around the cement works to monitor airborne smoke particles.
Particle size in mm Medical effect
Larger than 0.4 No medical risks known
0.3 and smaller Causes asthma attacks
0.2 and smaller May cause cancer
These four sensors only detect particle sizes larger than 0.5 mm and measure the concentration of particles in ppm. The scientists reported that the particle sensors showed that the average concentration of particles was 1.8 ppm. The scientists concluded that there was no risk to health.
Page 16 of 31
(i) Explain why the local residents objected to the positions of the four sensors.
The diagram shows a self-heating can designed to raise the temperature of coffee to 60 °C.
The button on the base of the can is pushed. The foil separator breaks, allowing water to mix with the quicklime. After about 3 minutes, the can is opened by the ring pull. Insulating materials are used inside the walls of the can to prevent either the lips or the fingers from being burned.
(causes) acid rain (1) do not accept nitrogen or water vapour for emissions do not accept no named emission
1
(ii) absorb / trap / capture / filter / pass through water / scrub / electrostatic attraction ignore condense / off setting / different fuel
1 [6]
Page 22 of 31
M2. clay 1
limestone 1
water 1
[3]
M3. (a) limestone clay
both for 1 mark 1
(b) water sand crushed rock
for 1 mark each 1
[4]
M4. (a) (i) clay
for one mark
(ii) calcium oxide / quicklime / CaO for one mark
(iii) sensible answers such as cost of fuel etc. / accept a wide range of appropriate answers
for one mark 3
(b) sand gravel (owtte) e.g. crushed rock water
any two for 1 mark each 2
[5]
M5. (a) 1 / one 1
3 / three 1
Page 23 of 31
(b) (i) (wear safety) glasses / masks / gloves accept do not handle hot objects / use tongs or accept other safety points such as, ‘tie hair back’
1
(ii) calcium oxide accept quicklime
1
(iii) carbon dioxide / CO2 is given off
accept a gas is given off 1
(d) (i) any two from:
• dust / atmospheric pollution
• noise
• eyesore
• destroys habitats
• (extra) traffic
• any other named pollution or description of pollution 2
(ii) any one from:
• employment
• increases local trade / makes money
• future development of quarry recreation / park / lake / reservoir do not accept cheaper houses / land / new roads
1 [8]
M6. (a) (i) 1 1
3 1
(ii) nucleus 1
electron 1
Page 24 of 31
(b) (i) methane / CH4
accept natural gas ignore air do not allow other gases
1
(ii) carbon dioxide 1
(c) (i) any two from:
• medical risks
• asthma
• cancer
• dirt
• causes global warming / global dimming / greenhouse effect / acid rain ignore death accept effect on health accept difficulty breathing/ lung disease allow smoke particles allow harmful for the environment
2
(ii) any two from:
• have a test done / scientific evidence
• independent (evidence)
• comparison of smoke particles / when different fuels used
• medical evidence or more / less asthma attacks or cancer or dirt on cars
2 [10]
M7. (a) calcium carbon oxygen
2 correct for 1 mark 3 correct for 2 marks
2
(b) cement glass
each for 1 mark 2
Page 25 of 31
(c) (i) allows coal to bum / flushes out CO2
for 1 mark 1
(ii) produced by burning coal produced by decomposition of limestone
each for 1 mark 2
(d) (i) calcium oxide + water → calcium hydroxide or quicklime + water → slaked lime
for 1 mark (allow composite equation from these two)
1
(ii) to neutralise it / because it is alkaline or basic for 1 mark
1 [9]
M8. (a) causes dust pollution 1
increases traffic 1
(b) (i) decomposition 1
(ii) 44(g) 1
(c) (calcium) hydroxide 1
(calcium) carbonate 1
substances must be in the order shown [6]
M9. (a) calcium oxide 1
calcium hydroxide 1
calcium carbonate 1
substances must be in the order shown
Page 26 of 31
(b) (i) strength of mortar decreases (as volume of sand increases) 1
(ii) 400 (cm3)
1
any one from:
• 37cm is an anomalous result/should be 42cm
• most results/pattern change by 6cm 1
(c) contains aggregate accept bonding is stronger
1 [7]
M10. (a) (i) oxygen / air reacts with carbon / methane (to form carbon dioxide)
accept from the decomposition / reaction of calcium carbonate ignore CO
2 from the air
1
nitrogen is (unreacted) from the air 1
(ii) CaO 1
CO2
any order ignore words any incorrect balancing max 1 mark
1
(b) any one from:
• more energy / efficient allow converse for present fuel
• from a sustainable / renewable resource
• produces less / no carbon dioxide / greenhouse gases / global warming ignore no pollution / environmental damage
• more profit or money for local economy
accept fuel is cheap(er)
• more readily available it = different fuel
1
Page 27 of 31
(c) (i) any two from:
• not near where people / residents live accept not between cement works and where people live ignore sensors are unsightly
• not positioned where concentration of particles was likely to be highest
• not positioned downwind 2
(ii) the average / concentration was 1.8(ppm) or the average / concentration was below 2(ppm)
accept 1.8(ppm) is less than 2.0 (ppm) 1
(iii) any three from:
• children / people suffering asthma attacks
• result was an average
• readings (at some (2/3) sensors) could have been higher than 2ppm
• sensors did not detect particles below 0.5mm
• small particles / particles below 0.5mm / 0.4mm / 0.3mm / 0.2mm could (still) cause cancer / asthma ignore global dimming or cars becoming dirty or position of sensors
3 [11]
M11. (a) (i) calcium oxide / quicklime
allow calcium monoxide do not accept calcium dioxide ignore chemical formulae
1
Page 28 of 31
(ii) any three from:
• carbon dioxide / CO2
• (carbon dioxide) reacts (with the calcium hydroxide / slaked lime / plaster) allow reaction 3 identified do not allow incorrect reaction ignore mixes, unless they state the correct product
• limestone / calcium carbonate / CaCO3 forms
allow marble / chalk
• water is lost / evaporates it = plaster allow moisture ignore dries
3
(b) (i) as the amount / volume of sand decreases the strength of the mortar increases
accept as sand decreases the mortar is stronger / harder to crack allow as sand decreases the mortar increases allow converse ignore references to height of metal ball
1
(ii) any two from:
• 400 / 5th result is anomalous
accept two results (36 and 37 / 400 and 500 / 4th and 5th) are almost the same accept result at 400 should be 42
• the interval between the others is similar or the interval is about 6/7 allow the other results fit a pattern / are on a straight line
• he has only one set of results allow he has only done it once ignore reliable
2 [7]
M12. (a) (i) calcium oxide / CaO 1
carbon dioxide / CO2
products can be in either order ignore chemical names other than calcium oxide or carbon dioxide
energy / heat released / exothermic ignore gets hot / heats up if neither mark awarded then allow ‘mixing the chemicals heats up the coffee’ for 1 mark
1
(ii) any two from:
• foil has been broken(*)
• ring pull used(*) (*)if neither mark awarded accept ‘cannot / difficult to repair’ for 1 mark ignore button pushed
• quicklime and / or water mixed / reacted accept reaction not reversible accept cannot / difficult to replace quicklime / water / chemicals
2 [7]
M13. (a) (i) heat (the limestone)
accept decompose limestone accept heat with coke
1
add water / slake
dependent on 1st mark unless they say add water to the calcium oxide
1
(ii) magnesium hydroxide + hydrochloric acid
1
→ magnesium chloride + water / H2O
1 mark for each side of the equation (if a symbol equation is given then give 1 mark for correct formulae (all) and 1 mark for balancing)