Question :-
Water is a :-
a) Indicator
b) acid
c) base
d) Neutralised solution
e) None of these
Answers
Explanation:
Water is a compound of hydrogen and oxygen. Water is a pure substance and not a mixture. Water forms whenever two or more atoms form chemical bonds with each other. The chemical formula for water is H2O, that is each molecule of water consists of one oxygen atom chemically bonded to two hydrogen atoms.
Question 1:
Which of the following is not an acid-base indicator?
(a) blue litmus
(b) methyl orange
(c) phenolphthalein
(d) Digene
ANSWER:
(d) digene
Digene is not an acid–base indicator but an antacid (base). It is used as a medicine to reduce acidity of the stomach by neutralising it.
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Question 2:
Which of the following is a strong acid?
(a) nitric acid
(b) citric acid
(c) acetic acid
(d) tartaric acid
ANSWER:
(a) nitric acid
Nitric acid is highly corrosive in nature. It can burn our skin severely.
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Question 3:
Which of the following is not a base?
(a) sodium hydroxide
(b) magnesium hydroxide
(c) copper carbonate
(d) ammonium hydroxide
ANSWER:
(c) copper carbonate
Copper carbonate is not a base but an ionic salt.
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Question 4:
Which of these metals cannot be used to prepare hydrogen by the action of an acid?
(a) sodium
(b) iron
(c) calcium
(d) copper
ANSWER:
(d) copper
Copper is a less reactive metal; therefore, it cannot displace and liberate hydrogen from acids.
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Question 5:
What is the common name of sodium bicarbonate?
(a) phitkari
(b) caustic soda
(c) baking soda
(d) blue vitriol
ANSWER:
(c) baking soda
Baking soda is the common name for sodium bicarbonate.