Acids, Bases and Salts Class 7 Quiz Question with Answer
Acids, Bases and Salts Class 7 Quiz Question with Answer. CBSE Class 7 Science Lesson 5 Mock Test.
Multiple choice questions
1.) Which is the taste of lemon and orange juice?
a) Sweet
b) Sour
c) Bitter
d) Salty
Answer: – b) Sour.
Explanation: – Lemon and orange juice’s taste is sour, because both these substances contain acid.
2.) What is the meaning of Acer?
a) bitter
b) sour
c) both (a) and (b)
d) none
Answer: – b) sour
Explanation: – It is a latin word – Acer means sour in taste.
3) The word acid has came from?
a) French word
b) Latin word
c) Italic word
d) none of these
Answer: – b) Latin word
Explanation: – Acid is originated from latin word acre. Acre has meaning which is sour in taste.
4) What is the taste of baking soda?
a) bitter
b) sour
c) both a and b
d) none of these
Answer:- a) bitter
Explanation :- Acids are not present in baking soda. Baking soda’s taste is bitter because it contains a base.
5) The Indicator lichens are extracted from which of the following organisms?
a) lichen
b) algae
c) cuscuta
d) green plant
Answer:- a) lichen
Explanation: – The indicator lichen is extracted from organism lichen, and not from algae, cuscuta or green plant.
6.) When litmus paper is added to an acidic solution then litmus paper turns into which color?
a) blue
b) red
c) purple
d) none of these
Answer:- b) red
Explanation: – Litmus paper turns red when it is added to acidic solution, while it turns blue when it is added to the basic solution .
7) Which of the following substances is acidic?
a) vinegar
b) lemon
c) curd
d) all of these
Answer:- d) all of these
Explanation: – vinegar, lemon and curd are sour in taste it means acid is present in this substance so, they all are acidic in nature. While the bitter taste proves that the substance has base present in it.
8) Which of the following acids is present in the ant’s sting?
a) acetic acid
b) formic acid
c) Tartaric acid
d) lactic acid
Answer :- b) formic acid
Explanation: – Formic acid is found in ant’s sting, acetic acid is found in vinegar, tamarind, and grapes , tartaric acid and while the lactic acid is found in curd.
9) Which acid is present in the human stomach?
a) oxalic acid
b) hydrochloric acid
c) formic acid
d) lactic acid
Answer: – b) hydrochloric acid
Explanation: – Our stomach contains hydrochloric acid; it helps us to digest food. Besides digestion it helps to eradicate bacteria and viruses from the stomach.
10) Excessive use of chemical fertilizers makes the soil______________.
a) basic
b) acidic
c) neutral
d) salty
Answer: – b) acidic
Explanation: – The excessive use of chemically formed fertilizers can increase the acidity of the soil and thus make it acidic in nature.
11) Which of the following statements is incorrect?
a) acid are sour to taste
b) base turn red litmus to blue
c) base are sweet in taste
d) ammonia has basic nature
Answer: – c) base are sweet in taste
Explanation: – all the above statements are correct except ‘statement c’ because bases are not sweet they have bitter taste.
12) Which of the following pair is incorrect –
a) stomach – hydrochloric acid
b) ant’s sting – Formic acid
c) soap – oxalic acid
d) lemon – citric acid
Answer :- c) soap – oxalic acid
Explanation: – Incorrect pair is (soap – oxalic acid) because soap is basic in nature, as it contains sodium hydroxide.
13) find odd one out from the following –
a) spinach , curd , vinegar
b) ant’s sting, lemon , citrus
c) soap , lime water , milk of magnesia
d) grapes , tamarind , aamla
Answer :- c) soap, lime water, milk of magnesia
Explanation: – soap, lime water, milk of magnesia are basic in nature while remaining are acidic in nature. So option (c) is odd among the above.
14) How many types of litmus paper are generally used?
a) three
b) two
c) four
d) five
Answer :- b) two
Explanation: – There are two types of litmus paper that show the acidic, basic and neutral nature of substance.
15) blue litmus paper remains blue when dipped in solution, that’s mean substance is
a) acidic
b) basic
c) neutral
d) none of these
Answer:- c) neutral
Explanation: – When litmus paper does not show any changes when dipped in solution that means solution is of neutral nature.
16) Which indicator is used for the titration?
a) phenolphthalein
b) turmeric
c) china rose
d) none of these
Answer :- a) phenolphthalein
Explanation: – For the titration process generally phenolphthalein indicator is used. While turmeric and China rose are natural indicators.
17) A natural indicator is obtained from which of the following substance?
a) turmeric
b) china rose
c) both a and b
d) none of these
Answer :- b) both a and b
Explanation: – Both turmeric and China rose can be used as indicators, both are natural indicators.
18) State the chemical name of the baking soda?
a) calcium hydroxide
b) magnesium hydroxide
c) sodium hydrogen carbonate
d) ammonium hydroxide
Answer: – c) sodium hydroxide carbonate
Explanation: – the chemical name of baking soda is sodium hydrogen carbonate.
19) The substance is neither acidic nor basic and is called
a) acidic
b) basic
c) neutral
d) none
Answer :- c) neutral
Explanation: – The solution which does not change its color, either red or blue litmus are known as neutral solutions.