Chemistry MCQ Questions Answers – Practice Set Part 3

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31) The method of concentrating the ore which makes use of the difference in density between ore and impurities is called

a) liquation

b) leaching

c) levigation

d) magnetic separation

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32) The most electropositive elements among the following is

a) Na

b) Ca

c) K

d) Cs

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33) The mass of P₄O₁₀ that will be obtained from the reaction of 1.33 gram of P₄ and 5.07 of oxygen is

a) 2.05 gram

b) 3.05 gram

c) 4.05 gram

d) 5.05 gram

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34) The inexpensive and commonly used variety of glass is called soda glass. It is called so because

a) was used initially for making bottles of soda(carbonated drink)

b) is made using soda(sodium carbonate)

c) was initially used for storing sodium carbonate

d) is made using soda lime

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35) Which one of the following is not used to dope a semiconductor

a) Al

b) B

c) In

d) Au

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36) Nylon is prepared from

a) Adipic acid and hexametheylene diamine

b) Ethylene glycol and nitric acid

c) Hexametheylene diamine and phthalic acid

d) Ethylene clycol and adipic acid

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37) Due to rusting the weight of iron?

a) decreases

b) increases

c) remains the same

d) uncertain

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38) The number of electrons presents in H⁺ is

a) zero

b) one

c) two

d) three

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39) The inert gases are ____ in water

a) sparingly soluble

b) insoluble

c) soluble

d) None of these

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40) The ionic radii of N^3-, O^2-, F^– and Na⁺ follows the order

a) N^3- > O^2- > F^– > Na⁺

^b) N^3- > Na⁺ > O^2- > F^–

^c) Na⁺ > O^2- > N^3- > F^–

^d) O^2- > F^– > Na⁺ > N^3-