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Metals and Non-metals

Exemplar Problems

MCQ 3

Generally, non-metals are not lustrous. Which of the following nonmetal is lustrous?

1. Sulphur
2. Oxygen
3. Nitrogen
4. Iodine
   Answer: (d) Iodine

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Which one of the following four metals would be displaced from the solution of its salts by other three metals?

1. Mg
2. Ag
3. Zn
4. Cu
   Answer: (b) Ag

2 mL each of concentrated HCl, HNO₃ and a mixture of concentrated HCl and concentrated HNO₃ in the ratio of 3 : 1 were taken in test tubes labelled as A, B and C. A small piece of metal was put in each test tube. No change occurred in test tubes A and B but the metal got dissolved in test tube C respectively. The metal could be

1. Al
2. Au
3. Cu
4. Pt
   Answer: (b) Au

An alloy is

1. an element
2. a compound
3. a homogeneous mixture
4. a heterogeneous mixture
   Answer: (c) A homogeneous mixture

An electrolytic cell consists of

1. positively charged cathode
2. negatively charged anode
3. positively charged anode
4. negatively charged cathode

1. (i) and (ii)
2. (iii) and (iv)
3. (i) and (iii)
4. (ii) ad (iv)
   Answer: (b) (iii) and (iv)

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During electrolytic refining of zinc, it gets

1. deposited on cathode
2. deposited on anode
3. deposited on cathode as well as anode
4. remains in the solution
   Answer: (a) Deposited on cathode

An element A is soft and can be cut with a knife. This is very reactive to air and cannot be kept open in air. It reacts vigorously with water. Identify the element from the following

1. Mg
2. Na
3. P
4. Ca
   Answer: (b) Na

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Alloys are homogeneous mixtures of a metal with a metal or nonmetal. Which among the following alloys contain non-metal as one of its constituents?

1. Brass
2. Bronze
3. Amalgam
4. Steel
   Answer: (d) Steel

Which among the following statements is incorrect for magnesium metal?

1. It burns in oxygen with a dazzling white flame
2. It reacts with cold water to form magnesium oxide and evolves hydrogen gas
3. It reacts with hot water to form magnesium hydroxide and evolves hydrogen gas
4. It reacts with steam to form magnesium hydroxide and evolves hydrogen gas
   Answer: (b) It reacts with cold water to form magnesium oxide and evolves hydrogen gas

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