Q1.Which one of the following is the correct sequence of the given elements in the increasing order of their reactivity?
(d) Iodine-Bromine-Fluorine-Chlorine Q2. Which one of the following laws explains the formation of carbon monoxide and carbon dioxide from carbon and oxygen?
(a) Law of conservation of mass
(b) Law of multiple proportions
(c) Law of reciprocal proportions
(d) Law of definite proportions Q3. Which of the following is the best example of the law of conservation of mass?
(a) When 12 gm of carbon is heated in vacuum, there is no change in mass
(b) Weight of platinum wire is the same before and after heating
(c) A sample of air increases in volume when heated at constant pressure but mass remains unchanged
(d) 12 gm of carbon combines with 32 gm of oxygen to give 44 gm of carbon dioxide.Q4. Which one among the following transitions of electron of hydrogen atom emits radiation of the shortest wavelength?
(a) n = 2 to n = 1
(b) n = 3 to n = 2
(c) n = 4 to n = 3
(d) n = 5 to n = 4Q5. Which of the statements regarding carbon dioxide is /are correct?
It is prepared on large scale by the action of water on lime.
2. In the solid form it can be used as a refrigerant. Select the correct answer using the code given below:
(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2 8. Vinegar is the trade name of Q6. The acid contained in vinegar is
(a) acetic acid
(b) ascorbic acid
(c) citric acid
(d) tartaric acid Q7. Which among the following elements (metals) pollutes the air of a city having large number of automobiles?
(d) NickelQ8. When aqueous solutions of two salts are mixed, the third salt formed may appear as a solid precipitate or a clear solution depending upon the solubility of its ions. It is observed that all salts of Na, K, NH4 are soluble. All nitrates and bicarbonates are also soluble. All halides (chlorides, bromides, iodides) are soluble except those of Ag, Hg (I) and Pb. All sulphates are soluble except those of Ag, Ca, Ba and Pb. Which one among the following combinations of solutions will produce a solid precipitate?
(a) Sodium sulphate and barium chloride
(b) Magnesium sulphate and barium bicarbonate
(c) Lithium iodide and barium chloride
(d) Ammonium sulphate and potassium bromideQ9. A glass of water does not turn into ice as it reaches 0 °C. It is because
(a) water does not solidify at 0°C
(b) a certain amount of heat must be supplied to the glass of water so as to solidify
(c) a certain amount of heat must be taken out from the glass of water so as to solidify
(d) water solidifies at 0K onlyQ10. Which one of the following is not contained in Portland cement?
(d) Ca3(PO4)2 Q11. What is the composition of nitrolim – a chemical fertilizer?
(a) Nitrogen and limestone
(b) Calcium carbide and nitrogen
(c) Calcium carbide and carbon
(d) None of the above Q12. The best and the poorest conductors of heat are respectively
(a) silver (Ag) and lead (Pb)
(b) copper (Cu) and aluminium (Al)
(c) silver (Ag) and gold (Au)
(d) copper (Cu) and gold (Au)
1. (a)2. (b)3. (a)4. (a)5. (d)6. (a)7. (b)8. 9. (c)10. (d)11. (d)12. (a)