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Which of the following non-metals is a liquid? (a) Carbon (b) Bromine (c) Phosphorus (d) Sulphur

Answer: (b) Bromine At room temperature, bromine is the only non-metal that is a liquid and a diatomic molecule. It is a thick, reddish-brown... View Article

Electrical wires have a coating of an insulating material. The material, generally used is (a) Sulphur (b) Graphite (c) PVC (d) All can be used

Answer: (c) PVC PVC is an insulator so to prevent us from getting electric shocks wires are coated with PVC. Electric wires are made of... View Article

Generally, non-metals are not conductors of electricity. Which of the following is a good conductor of electricity? (a) Diamond (b) Graphite (c) Sulphur (d) Fullerene

Answer: (b) Graphite Graphite is an exception to the rule that non-metals do not conduct heat or electricity. Graphite is an allotropic type of... View Article

Although metals form basic oxides, which of the following metals form an amphoteric oxide? (a) Na (b) Ca (c) Al (d) Cu

Answer: (c) Al An amphoteric oxide is an oxide that can act either as an acid or as a base to create salt and water in a reaction. The... View Article

The electronic configurations of three elements X, Y and Z are X — 2, 8; Y — 2, 8, 7 and Z — 2, 8, 2. Which of the following is correct? (a) X is a metal (b) Y is a metal (c) Z is a non-metal (d) Y is a non-metal and Z is a metal

Answer: (d) Y is a non-metal and Z is a metal X = 1s2 2s2 2p6 = 2, 8 = 10 It is the electronic configuration of neon. Y = 1s2 2s2 2p6 3s2 3p5 =... View Article

Reaction between X and Y, forms compound Z. X loses electron and Y gains electron. Which of the following properties is not shown by Z? (a) Has a high melting point (b) Has a low melting point (c) Conducts electricity in molten state (d) Occurs as solid

Answer: (b) Has a low melting point Because X loses electrons, it is an electropositive metal, whereas Y gains electrons, making it a non-metal.... View Article

Which among the following alloys contain mercury as one of its constituents? (a) Stainless steel (b) Alnico (c) Solder (d) Zinc amalgam

Answer: (d) Zinc amalgam A zinc amalgam is a mixture of mercury (ten per cent) and zinc (90 per cent). One of the ingredients in it is mercury.... View Article

Which among the following statements is incorrect for magnesium metal? (a) It burns in oxygen with a dazzling white flame (b) It reacts with cold water to form magnesium oxide and evolves hydrogen gas (c) It reacts with hot water to form magnesium hydroxide and evolves hydrogen gas (d) 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 Magnesium reacts with cold water to form magnesium oxide... View Article

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? (a) Brass (b) Bronze (c) Amalgam (d) Steel

Answer: (d) Steel Steel is an alloy made up of carbon and iron where carbon is a non-metal. Alloys are metal mixtures with other elements whose... View Article

An element A is soft and can be cut with a knife. This is very reactive to air and cannot be kept open in the air. It reacts vigorously with water. Identify the element from the following (a) Mg (b) Na (c) P (d) Ca

Answer: (b) Na Sodium is an alkali metal and is so soft that it can be easily cut by knife. Soft metals are those which can be cut and easy to... View Article

During electrolytic refining of zinc, it gets (a) deposited on cathode (b) deposited on anode (c) deposited on the cathode as well as anode (d) remains in the solution

Answer: (a) deposited on the cathode Zinc is positively charged hence it moves towards the negatively charged cathode. Electrolytic refining is... View Article

An electrolytic cell consists of (i) positively charged cathode (ii) negatively charged anode (iii) positively charged anode (iv) negatively charged cathode (a) (i) and (ii) (b) (iii) and (iv) (c) (i) and (iii) (d) (ii) ad (iv)

Answer: (b) (iii) and (iv) The three main components of electrolytic cells include the cathode, the anode, and the electrolyte. In most... View Article

An alloy is (a) an element (b) a compound (c) a homogeneous mixture (d) a heterogeneous mixture

Answer: (c) a homogeneous mixture An Alloy is a homogeneous mixture because its composition is uniform. A homogeneous mixture is a mixture... View Article

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 (a) Al (b) Au (c) Cu (d) Pt

Answer: (b) Au Solution C is a mixture of concentrated HCl and concentrated HNO3 which is called aqua regia. Aqua Regia dissolves gold. Aqua... View Article

Which one of the following four metals would be displaced from the solution of its salts by the other three metals? (a) Mg (b) Ag (c) Zn (d) Cu

Answer: (b) Ag Because silver is a non-reactive metal it can be displaced easily. Mg, Zn, or Cu metals would displace Ag from the solution of... View Article

Generally, non-metals are not lustrous. Which of the following nonmetal is lustrous? (a) Sulphur (b) Oxygen (c) Nitrogen (d) Iodine

Answer: (d) Iodine Iodine with the symbol ‘I’ is a dark gray or purple blackish nonmetallic element with atomic number 53 in the Periodic Table.... View Article

Which of the following metals are obtained by electrolysis of their chlorides in molten state? (i) Na (ii) Ca (iii) Fe (iv) Cu (a) (i) and (iv) (b) (iii) and (iv) (c) (i) and (iii) (d) (i) and (ii)

Answer: (d) (i) and (ii) Sodium and calcium are metals that are produced through electrolysis of their molten chlorides. Both metals are... View Article

Generally, metals are solid in nature. Which one of the following metals is found in liquid state at room temperature? (a) Na (b) Fe (c) Cr (d) Hg

Answer: (d) Hg Except for mercury, all metals are solid at normal temperature. At room temperature, mercury metal is a liquid. Mercury is a... View Article

If copper is kept open in the air, it slowly loses its shining brown surface and gains a green coating. It is due to the formation of (a) CuSO4 (b) CuCO3 (c) Cu(NO3 ) 2 (d) CuO

Answer: (b) CuCO3 Copper forms a green deposit on its surface when exposed to air which is usually a mixture of copper carbonate and copper... View Article

Stainless steel is a very useful material for our life. In stainless steel, iron is mixed with (a) Ni and Cr (b) Cu and Cr (c) Ni and Cu (d) Cu and Au

Answer: (a) Ni and Cr Stainless steel is an alloy of Iron, Nicker and chromium. This alloy makes the metal strong, durable and... View Article

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