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1. Which of the following substances is not acidic?
A. Lemon juice
C. Baking powder
B. Vinegar
D. Orange juice
2. Which of the following substances has a pH of 7?
A. Vinegar
C. Lemon juice
B. Bleach
D. Water
3. Which of the following substances has the lowest pH?
A. Toothpaste
C. Water
B. Milk
D. Lemon
4. What is litmus?
A. An acid
C. An alkali
B. An indicator
D. A neutral substance
5. Bananas are an example of a ____________.
A. strong alkali
C. strong acid
B. weak alkali
D. weak acid
6. What colour does universal indicator turn when added to strong acid?
A. White
C. Green
B. Clear
D. Red
7. A liquid has a pH of 8. What does this mean?
A. It is weakly acidic
C. It is strongly acidic
B. It is weakly alkaline
D. It is strongly alkaline
8. What pH does a neutral substance have? Give an example of neutral substance.
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9. Describe the terms below by your own words.
a. Corrosive:
b. Acid:
c. Neutralisation:
d. pH scale:
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10. Litmus is an example of an indicator. It turns different colours in acids and alkalis.
Litmus turns ____________ if it is an acid and it turns ____________ if it is in an
alkali.
When an acid and an alkali react together they produce a ___________ solution.
This has a pH of ____________. This type of reaction is called _____________.
11. State the meaning of the following hazard symbols
12. Fill in the table below. Name at least 3 acids and 3 alkalis.
Acids
Alkalis
13. State whether the following substances are acids, alkalis or neutral substances. If
they are an acid or an alkali, you should also say if they are strong or weak.
a.
A substance with pH 3
___________________
b.
A liquid with pH 8
___________________
c.
A chemical with pH 7
___________________
d.
A substance with pH 14
___________________
e.
A substance which turns universal indicator yellow ___________________
f.
A substance which turns universal indicator blue
___________________
14. Draw your own pH scale below. Include numbers, labels and at least 3 examples
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15. Bees and wasps are insects which use a sting to defend
themselves. A wasps sting has a pH of 10 and a bee sting
has a pH of 2.
a. Copy and complete the following table about wasp and
bee stings.
Acid and alkaline?
What colour would you see
with universal indicator?
Wasp sting pH 10
Bee sting pH 2
b. What would you add to a wasp sting to neutralise it and stop it from hurting?
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16. The table below shows the pH of four different soil samples which are labelled A – D.
Soil sample
pH of soil
A
5.0
B
7.4
C
7.0
D
4.7
a. Which soil sample is neutral? ...............................................................................
b. Cabbage grows better in an alkaline soil. Which soil sample would be the best to
grow cabbage in? ..................................................................................................
c. Potatoes grow better in slightly acidic soil. Which soil sample would be the best to
grow potatoes in? ..................................................................................................