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Published on: 28/08/2019
Acids, Bases and Salts
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Questions + Answers key
Take MCQ Science Test
1.
The medicine used for treating indigestion is:
Antibiotic
Anti-acid
Antacid
Analgesic
2.
Sodium hydroxide is
A base
An alkali
Bitter in taste
All of these
3.
Raw mango is sour in taste due to presence of
Tartaric acid
Citric acid
Formic acid
Oxalic acid
4.
Stomach secretes:
HCl
H2SO4
CH3COOH
NaOH
5.
Sting of an ant contains
Vinegar
Common salt
Formic acid
Milk of magnesia
6.
Neutralisation reaction is a
physical and reversible change
physical change that cannot be reversed
chemical and reversible change
chemical change that cannot be reversed
7.
When the soil is too basic, plants do not grow well in it. To improve its quality, what must be added to the soil?
Organic matter
Quicklime
Slaked lime
Calamine solution
8.
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
9.
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
10.
Consider the following statements:
(i) Both acids and bases change colour of all indicators.
(ii) If an indicator gives a colour change with an acid, it does not give a change with a base.
(iii) If an indicator changes colour with a base, it does not change colour with an acid.
(iv) Change of colour with an acid and a base depends on the type of the indicator.
Which of the above statements is/are correct?
Only (iv)
(i) and (iv)
(ii) and (iii)
All of these
11.
Ammonium chloride is an example of _____________salt
12.
_____________is used to remove acidity of solids
13.
Acetic acid is present in __________ while __________ is present in lemon.
14.
When an acid mixed with a base, a __________ reaction takes place.
15.
Acid + Base \(\longrightarrow\) _____________ + Water
16.
Lemon water is basic in nature.
17.
Calamine can be used to treat ant's sting.
18.
Phenolphthalein is a natural indicator.
19.
Common salt dissolved in water turns blue litmus red.
20.
Lime water turns red litmus blue.
21.
Lime water
22.
Soap
23.
Turmeric
24.
Milk of magnesia
25.
Sodium chloride
26.
Name two substances which changes red litmus blue.
27.
Name two natural occurring indicators
28.
What are indicators?
29.
What are bases?
30.
What are acids?
1.
(c)
Antacid
2.
(d)
All of these
3.
(a)
Tartaric acid
4.
(a)
HCl
5.
(c)
Formic acid
6.
(d)
chemical change that cannot be reversed
7.
(a)
Organic matter
8.
(d)
colourless and pink
9.
(b)
Yellow in acid and red in base
10.
(a) All indicators do not change colour with acids as well as bases, e.g. turmeric changes its colour to pink with the base but it remains yellow with acid.
Therefore, statement (i) is incorrect. There are some indicators which change colour with both acid and base, e.g. methyl orange, litmus, thus statement (ii) and (iii) are also incorrect. Statement (iv) is the correct conclusion about indicators.
11.
( )
acidic
12.
( )
Slaked lime
13.
( )
vinegar, citric acid
14.
( )
neutralisation
15.
( )
salt
16.
(b)
17.
(a)
18.
(a)
19.
(b)
20.
(a)
21.
( )
Turns china rose green
22.
( )
Red litmus blue
23.
( )
is used as indicator
24.
( )
Changes red litmus blue
25.
( )
major salt of sea
26.
( )
Sodium hydroxide, magnesium hydroxide
27.
( )
Litmus and turmeric are natural occurring indicators
28.
( )
Indicators are the substances that are used to test the acidity or basicity of a substance
29.
( )
Substances which are bitter in taste and soapy to touch are called bases
30.
( )
Substances which are sour in taste are called acids.
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