Problem 126
The reaction of slaked lime with \(\mathrm{Cl}_{2}\) gas gives: (a) A mixture of \(\mathrm{Ca}(\mathrm{OCl})_{2}, \mathrm{Ca}(\mathrm{OH})_{2}, \mathrm{CaCl}_{2}\) and \(\mathrm{H}_{2} \mathrm{O}\) (b) Quick lime (c) Baryta water (d) Only \(\mathrm{Ca}(\mathrm{OCl})_{2}\)
Problem 127
Halides of alkaline earth metals form hydrates such as \(\mathrm{MgCl}_{2} \cdot 6 \mathrm{H}_{2} \mathrm{O}, \quad \mathrm{CaCl}_{2} \cdot 6 \mathrm{H}_{2} \mathrm{O}, \quad \mathrm{BaCl}_{2} \cdot 2 \mathrm{H}_{2} \mathrm{O}\) and \(\mathrm{SrCl}_{2} \cdot 2 \mathrm{H}_{2} \mathrm{O}\). This shows that halides of group 2 elements: (a) Can absorb moisture from air (b) Act as dehydrating agents (c) Are hydroscopic in nature (d) All of the above
Problem 128
The relative thermal stabilities of alkali metal halides are such that: (a) \(\mathrm{CsCl}>\mathrm{RbCl}>\mathrm{KCl}<\mathrm{NaCl}>\mathrm{LiCl}\) (b) \(\mathrm{CsCl}>\mathrm{RbCl}<\mathrm{KCl}>\mathrm{NaCl}<\mathrm{LiCl}\) (c) \(\mathrm{LiCl}>\mathrm{NaCl}>\mathrm{KCl}>\mathrm{RbCl}>\mathrm{CsCl}\) (d) \(\mathrm{Cs} \mathrm{Cl}>\mathrm{RbCl}>\mathrm{KCl}>\mathrm{NaCl}>\mathrm{LiCl}\)
Problem 129
A deliquescent white crystalline hydroxide \(X\) reacts with a nitrate \(\mathrm{Y}\) to form another hydroxide which decomposes to give a insoluble brown layer of its oxide. \(\mathrm{X}\) is a powerful cautery and breaks down then proteins of skin flesh to a pasty mass. \(\mathrm{X}\) and \(\mathrm{Y}\) are: (a) \(\mathrm{NaOH}, \mathrm{Zn}\left(\mathrm{NO}_{3}\right)_{2}\) (b) \(\mathrm{NaOH}, \mathrm{AgNO}_{3}\) (c) \(\mathrm{Ca}(\mathrm{OH})_{2} \cdot \mathrm{HgNO}_{3}\) (d) \(\mathrm{NaOH}, \mathrm{Al}\left(\mathrm{NO}_{3}\right)_{3}\)
Problem 130
The major role of fluorspar \(\left(\mathrm{CaF}_{2}\right)\) which is added in small quantities in the electrolytic reduction of alumina dissolved in fused cryolite \(\left(\mathrm{Na}_{3} \mathrm{AlF}_{6}\right)\) is 1\. As a catalyst 2\. To make the fused mixture very conducting 3\. To lower the temperature of melt 4\. To decrease the rate of oxidation of carbon at the anode (a) 2,3 (b) 1,2 (c) \(2,3,4\) (d) 3,4
Problem 131
Solution of sodium metal in liquid ammonia is strongly reducing due to the presence in solution of the following: (a) Solvated electrons (b) Sodium atoms (c) Sodium hydride (d) Sodium amide
Problem 132
Metal \(X\) on heating in nitrogen gas gives Y. Y on treatment with \(\mathrm{H}_{2} \mathrm{O}\) gives a colourless gas which when passed through \(\mathrm{CuSO}_{4}\) solution gives a blue colour. Y is: (a) \(\mathrm{MgO}\) (b) \(\mathrm{Mg}\left(\mathrm{NO}_{3}\right)_{2}\) (c) \(\mathrm{Mg}_{3} \mathrm{~N}_{2}\) (d) \(\mathrm{NH}_{3}\)
Problem 133
Bleaching powder loses its powder on keeping for a long time because: (a) It absorbs moisture (b) It changes into calcium chloride and calcium chlorate (c) It changes into calcium hypochlorate (d) It changes into calcium chloride and calcium hydroxide
Problem 134
On heating quick lime with coke in an electric furnace, we get (a) \(\mathrm{CaC}_{2}\) (b) \(\mathrm{CaCO}_{3}\) (c) \(\mathrm{CaO}\) (d) \(\mathrm{Ca}\) and \(\mathrm{CO}_{2}\)
Problem 135
Limestone is not used in which of the following manufacturing processes? (a) Portland cement (b) Phosphorus from phosphorite (c) Iron from haematite (d) Solvay process of sodium carbonate
