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SCIENCE 3.The Acid Base Chemistry WORK SHEET
Q1. Fill in the blanks.
1. Base that dissolve in water are called _____________.
Q2 Match the columns:
A B
(1) Turmeric (a) Tooth Enamel
(2) Calcium phosphate (b) Bitter
(3) Sodium bicarbonate (c) Anaesthetic
(4) Base (d) Detergent powder
(5) Bleaching powder (e) Indicator
(6) Chloroform (f) Alkaline
(g) Oxidizing agent
Q3.Find the pod man out:
1. Sugar cane, Vinegar, Tamarind, Kokum.
2. Eosin, Phenolphthalein, Litmus, Methyl orange.
3. H SO , HCL, NH OH , HNO
4. Sodium, potassium, calcium, gypsum.
Q4 State weather the following statements are true or false:
1. Chlorine is a strong disinfectant
2. Alkalies have H + ions.
3. When a drop of universal indicator is added to distilled water, it turns purple.
4. Antacids are acidic substances.
5. Common salt is an ionic compound.
6. The reaction between a base and an oxide of a nonmetal is neutralization.
7. Juice of rose petals or hibiscus can be used as indicators.
8. Baking soda is a brown amorphous powder.
9. In the symbol Ph, P stands for “power of”.
10. Alkalies do not react with metals.
11. A neutral substance has a pH of o (zero).
12. Rain water is neutral.
13. A solution of an alkali cannot conduct electricity.
14. Chloride lime has a strong odour of lemon juice.
15. Phenolphtalein remains colourless in an acid.
Q5 Write the molecular formula of each of the following:
(1) Baking soda (2) Chalk
(2) Common salt (4) Chloride of lime
(5) Slaked lime (6) Vinegar
. (7) Washing soda (8) Ammonium hydroxide
(9) Aluminium carbonate (10) Anhydrous copper sulphate
Q6. Name the following.
1. The acid produced in our stomach.
2. A gas that can turn lime water to milky colour.
3. Gas set free by bleaching powder when water is added to it.
4. A basic salt added to hard water to make it soft and potable.
5. A root vegetable, purple –coloured juice of which can be used as an indicator.
Q7. Answer each of the following in one sentence:
1. What does acidus mean?
2. What is universal indicator consist of?
3. What ions do acids contain?
4. What is a strong acid?
5. State the range of pH in a human body.
6. What is the chemical formula of red oxide used as a paint?
7. Name two salts that can be obtained using common salt as one of the raw materials.
8. What is fused salt?
9. Name two classes of compounds that can corrode metals.
10. What is ionization?
11. What is available chlorine?
12. State two uses of chloroform.
13. Give any two uses of sodium carbonate.
14. Name the substances that produce hardness in water.
15. What is saponification?
16. How is soap produced?
Q8 Give scientific reasons:
1. Lime water and butter having butyric acid can be used to treat acidity.
2. During electrolysis of solution, electric bulb glows when the electrodes are dipped in a
solution of dilute HCI but it does not glow when they are dipped in the solution of glucose (or
methyl alcohol).
3. To dilute sulphuric acid, we should not add water to the acid but add acid to water.
4. A bite a red ant or sting of a honey bee cause itching, irritation pain and swelling.
5. When few grains of copper oxide are dropped in a beaker containing water they do not
dissolve but maintain their black colour. However, when concentrated hydrochloric acid is
added to the beaker, a blue3coloured solution is obtained.
6. Bleaching powder must be stored in air-tight container.
7. Bleaching powder is often added to water in swimming pools or sprinkled on uncleared
garbage.
Q9 Complete the following equation and balance them when necessary.
1. Zn(s) + HCl(aq) →______________ + _______________
2. CuO(s) + HCl → ______________ + _______________
3. ___________ + NaOH(aq) → NaCl(aq) + ______________
4. Mg(s) + _____________ → MgSO4(aq) + H2(g)
5. Na2O(aq) + H2SO4(aq) → _____________ + _____________
6. Na2CO3(s)+ HCl → ______________ + H2O + ________________
Q10 Explain with a balanced chemical equation, what happen in each of the
following:
1. Aluminium carbonate is treated with dilute hydrochloric acid.
2. Dry slaked lime is exposed to chlorine gas.
3. Aluminium ribbon is heated with concentrated solution of sodium hydroxide.
4. Zinc granules are heated with a solution of concentrated sodium hydroxide.
5. Washing soda is treated with diluted hydrochloric acid.
Q11 Write brief answer to each of the following:
1. What colour changed do we observe in litmus papers whn they are exposed to acidic and basic
substance?
2. What colour changes are observed in methyl orange when we add it to acids and bases?
3. What colour change in phenopthalien solution help us to identify acids and bases?
4. Can we use phenopthalien to identify a neutral substance, say water, from a solution of an
acid?
5. What are olfactory indicators?
6. What are strong acids? Give two examples.
7. What are weak acids? Give two examples.
8. How does a tooth paste help in preventing tooth decay?
9. All alkalies are bases but all bases are not alkalies.
10. Rock salt and table salt, both, are two forms of sodium chloride.Yet they differ in their
colours.Explain.
Q12 Distin
