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Published on: 31/07/2019
Acids, Bases and Salts
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Questions + Answers key
Take MCQ Science Test
1.
Write three differences between an organic acid and a mineral acid.
2.
Describe the process of neutralisation with the help of an example.
3.
Is the distilled water acidic/basic/neutral? How would you verify it?
4.
Common salt dissolved in water turns blue litmus red.
5.
Lime water turns red litmus blue.
6.
A compound if acidic will turn all indicators red.
7.
Sodium hydroxide turns blue litmus to red.
8.
Nitric acid turns red litmus to blue.
9.
Which part of our body contains hydrochloric acid?
10.
Which acid does each cell in our body contains?
11.
Name the reaction when an acid is mixed with base.
12.
Is lime water an acidic or basic solution?
13.
Nitesh was playing with his friends in the garden. Suddenly, Nitesh was stung by a honeybee and was in great pain. Immediately, his friends call his mother. She applied baking soda solution on the affected area and then took him to the doctor.
Read the above passage and answer the following questions:
(a) What could be the reason for this burning pain?
(b) Why did his mother applied baking soda solution on the affected area?
(c) What values are shown by Nitesh's friends?
14.
Boojho, Paheli and their friend Golu were provided with a test, each containing China rose solution which was pink in colour. Boojho added 2 drops of solution 'A' in his test tube and got dark pink colour. Paheli added 2 drops of solution '8'to her test tube and got green colour. Golu added 2 drops of solution 'C' but could not get any change in colour. Suggest the possible cause for the variation in their results.
15.
Raw mango is sour in taste due to presence of
Tartaric acid
Citric acid
Formic acid
Oxalic acid
16.
Stomach secretes:
HCl
H2SO4
CH3COOH
NaOH
17.
Sting of an ant contains
Vinegar
Common salt
Formic acid
Milk of magnesia
18.
Phenolphthalein is a synthetic indicator and its colours in acidic and basic solutions respectively are
red and blue
blue and red
pink and colourless
colourless and pink
19.
Turmeric is a natural indicator. On adding its paste to acid and base separately, which colours would be observed?
Yellow in both acid and base
Yellow in acid and red in base
Pink in acid and yellow in base
Red in acid and blue in base
20.
Ammonium chloride is an example of _____________salt
21.
_____________is used to remove acidity of solids
22.
When an acid mixed with a base, a __________ reaction takes place.
23.
Acid + Base \(\longrightarrow\) _____________ + Water
24.
The substances which show different colours in acidic, basic and neutral solutions are called __________
25.
Fertilizer
26.
Curd
27.
Turmeric
28.
Milk of magnesia
29.
Sodium chloride
30.
How is salt formed?
31.
What is the chemical name of vitamin C?
32.
What are neutral substances/solutions?
1.
| Organic acid | Mineral acid |
|---|---|
| These acids are naturally occurring acids and are found in plants and animals. These contain- COOH as functional group as reactive part. These acids are week. Examples: Lactic acid, acetic acid, citric.acid. |
These are derived from the mineral of the earth These contain H+ ions as reactive part. These acids are strong. Examples: Hydrochloric acid, sulphuric acid, nitric acid. |
2.
The reaction between an acid and a base is known as neutralisation reaction. In this reaction, both acid and base cancel each other's effect. Neutralisation reaction results in the formation of salt and water. During this reaction, energy in the form of heat is evolved.
Acid + Base \(\longrightarrow\) Salt + Water + Heat \(\uparrow\)
e.g. when sodium hydroxide (NaOH) is added to hydrochloric acid (HCI), sodium chloride (NaCl) and water (H2O) are obtained.
NaOH + HCI \(\longrightarrow\) NaCI + H2O + Heat \(\uparrow\)
Sodium Hydrochloric Sodium Water
hydroxide Acid Chloride
3.
Distilled water is neither acidic nor basic. When we test its nature through litmus paper strips, we have found neither red nor blue changes in colour which verifies its neutral nature.
4.
(b)
5.
(a)
6.
(b)
7.
(b)
8.
(b)
9.
Stomach contains hydrochloric acid
10.
Each cell of our body contains deoxyribonucleic acid (DNA).
11.
Neutralisation reaction.
12.
Lime water (calcium hydroxide) is a basic solution.
13.
(a) The reason for this burning pain is honeybee sting which causes pain and irritation. This is due to the acidic liquid (formic acid) injected into the skin by the honeybee.
(b) The effect of acid can be neutralised by rubbing the affected area by baking soda solution which is a mild base.
(c) Nitesh's friends are caring, supportive and helpful.
14.
China rose (gudhal) is an acid-base indicator.
China rose solution in different medium shows following changes:
China rose + acid \(\longrightarrow\) Give dark pink colour, hence A is an acidic solution.
China rose + base \(\longrightarrow\) give green colour, hence B is a basic solution.
China rose + neutral \(\longrightarrow\) No change in colour, hence C is a neutral solution.
15.
(a)
Tartaric acid
16.
(a)
HCl
17.
(c)
Formic acid
18.
(d)
colourless and pink
19.
(b)
Yellow in acid and red in base
20.
( )
acidic
21.
( )
Slaked lime
22.
( )
neutralisation
23.
( )
salt
24.
( )
indicators
25.
( )
Potassium nitrate
26.
( )
Manufacture of washing soda
27.
( )
is used as indicator
28.
( )
Changes red litmus blue
29.
( )
major salt of sea
30.
( )
A salt is formed when acid reacts with a base.
31.
( )
Ascorbic acid
32.
( )
Substances which are neither acidic nor basic are called neutral substances/solutions
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