CHEMISTRY

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CHEMISTRY QUESTION BANK
Name: ................................
Q1. Compare boiling and evaporation. Write at least three points.
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Q2. Outline the terms:
i. Amorphous
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ii. Crystalline
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iii. Surface tension
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iv. Viscosity
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Q3. Apply your understanding of the way molecules move in hot liquids, explain why the liquid in the
thermometer goes up when placed in hot water.
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Q4. Apply your understanding of the way molecules move in cold liquids, explain why the liquid in the
thermometer goes up when placed in cold water.
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Q5. Using circles to represent water molecules, draw a model of the molecules in cold and hot water.
• Use motion lines to show the speed of the molecules.
• Consider the space between molecules in each temperature of water.
Q6.
(a)
Evaporation
Rose knows that water and vinegar evaporate.
Tick ONE box to show what evaporation means. Evaporation is the change from...
gas to liquid.
gas to solid.
liquid to solid.
liquid to gas.
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(b)
Rose sets up a test to find out if more water or more vinegar evaporates over 3 days.
She puts water in one container and vinegar in another container, like this:
Rose places both containers on the same windowsill.
(i)
Use the information above to describe ONE thing that is not fair in her test.
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(ii)
State why does it matter if her test is not fair?
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(c)
Rose changes her test to make it fair. She measures the volumes of water and vinegar twice
each day to see how much has evaporated.
The table below shows her results.
Day
Time
Volume of
Volume of
water (cm3) vinegar (cm3)
Monday
10am
3pm
100
99
100
98
Tuesday
10am
3pm
97
94
94
86
Wednesday
10am
3pm
91
89
82
80
Rose wanted to compare water and vinegar to find out which evaporated the most
over 3 days. Use Rose’s results to suggest a conclusion for her test.
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(d)
Rose notices that more water and vinegar evaporated between 10am and 3pm on Tuesday
than between the same times on Monday or Wednesday.
Suggest one possible reason why more water and vinegar evaporated on Tuesday.
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Q7. Washing day
(a) Some children have washed a jumper.
Explain why does the jumper feel heavier after it is washed?
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(b) The children want to find out how long the jumper takes to dry. They hang the jumper up to dry.
State the process that completely dries the jumper.
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(c) The children weigh the jumper every hour. They make a graph of their results.
How many hours did the jumper take to dry?
.....................................................…hours
(d) The children repeat their test the next day. They wash and dry the same jumper in the same
way. The jumper dries more quickly.
State one possible reason why the jumper dries more quickly when they repeat their test.
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(e) List two ways by which they made their test a fair one.
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(f) Explain how does wind speed and surface area of the jumper affect the speed of drying.
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Q8. Work out 1000C into Fahrenheit. Show your working.
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Q9. Work out 3650F into Celsius. Show your working.
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Q10. Work out 16870C into Kelvin. Show your working.
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