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chemistry igcse acapprinted 78 · PDF 78
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Q2. Four statements about photosynthesis are listed.
Chlorophyll is required for photosynthesis.
The equation for photosynthesis is C6H12O6 + 6O2 → 6CO2 + 6H2O.
Photosynthesis requires energy from light.
Photosynthesis releases carbon dioxide, which can lead to climate change.
Which statements are correct?
1 and 3
1 and 4
2 and 3
2 and 4
Q3. Several processes are used to treat domestic water. Which row identifies a reason for the given
process?
Process
Reason
A
B
C
D
Chlorination
Filtration
Sedimentation
Use of Carbon
Removes impurities
Removes insoluble solids
Removes soluble solids
Kills bacteria
4. Which compounds both contribute to acid rain?
Carbon monoxide and carbon dioxide
Carbon monoxide and oxides of nitrogen
Oxides of nitrogen and sulfur dioxide
Sulfur dioxide and carbon dioxide
Q5. Which statements about water are correct?
Tap water has fewer impurities than distilled water.
Tap water will turn anhydrous cobalt(II) chloride pink.
The domestic water supply is treated with carbon to kill microbes.
Phosphates from fertilisers can cause deoxygenation of water.