Problem 169
Which one of the following ores is best concentrated by froth-floatation method? (a) cassiterite (b) galena (c) malachite (d) magnetite
Problem 170
Excess of KI react with \(\mathrm{CuSO}_{4}\) solution and then \(\mathrm{Na}_{2} \mathrm{~S}_{2} \mathrm{O}_{3}\) solution is added to it. Which of the following statements is incorrect for this reaction? [2004] (a) \(\mathrm{Cu}_{2} \mathrm{I}_{2}\) is formed (b) \(\mathrm{Na}_{2} \mathrm{~S}_{2} \mathrm{O}_{3}\) is oxidized (c) \(\mathrm{CuI}\), is formed (d) Evolved \(\mathrm{I}_{2}\) is reduced
Problem 171
Among the properties (A) reducing (B) oxidizing (C) complexing, the set of properties shown by \(\mathrm{CN}\) - ion towards metal species is [2004] (a) A, B (b) \(\mathrm{B}, \mathrm{C}\) (c) \(\mathrm{C}, \mathrm{A}\) (d) \(\mathrm{A}, \mathrm{B}, \mathrm{C}\)
Problem 172
During the process of electrolytic refining of copper some metals present as impurity settle as anode mud. These are \(\quad[\mathbf{2 0 0 5}]\) (a) \(\mathrm{Ag}\) and \(\mathrm{Au}\) (b) \(\mathrm{Pb}\) and \(\mathrm{Zn}\) (c) \(\mathrm{Fe}\) and \(\mathrm{Ni}\) (d) \(\mathrm{Sn}\) and \(\mathrm{A} \mathrm{g}\)
Problem 173
Heating mixture of \(\mathrm{Cu}_{2} \mathrm{O}\) and \(\mathrm{Cu}_{2} \mathrm{~S}\) will give (a) \(\mathrm{Cu}+\mathrm{SO}_{2}\) (b) \(\mathrm{Cu}+\mathrm{SO}_{3}\) (c) \(\mathrm{CuO}+\mathrm{CuS}\) (d) \(\mathrm{Cu}_{2} \mathrm{SO}_{3}\)
Problem 175
Which method of purification is represented by the following equation: \((\mathrm{s})+2 \mathrm{I}_{2}(\mathrm{~g}) \stackrel{523 \mathrm{~K}}{\longrightarrow} \mathrm{Ti} \mathrm{I}_{4}(\mathrm{~g}) \stackrel{120 \mathrm{~K}}{\longrightarrow} \mathrm{Ti}(\mathrm{s})+2 \mathrm{I}_{2}(\mathrm{~g})\) [2012] (a) Poling (b) Cupellation (c) Zone refining (d) Van Arkel
Problem 176
Iron exhibits \(+2\) and \(+3\) oxidation states. Which of the following statements about iron is incorrect? [2012] (a) Ferrous compounds are less volatile than the corresponding ferric compounds (b) Ferrous compounds are relatively more ionic than the corresponding ferric compounds. (c) Ferrous oxide is more basic in nature than the ferric oxide (d) Ferrous compounds are more easily hydrolysed than the corresponding ferric compounds
Problem 177
Which series of reactions correctly represents chemical relations related to iron and its compound? \([2014]\) (a) \(\mathrm{Fe} \stackrel{\mathrm{C}_{2} \text { heat }}{\longrightarrow} \mathrm{FeCl}_{3} \stackrel{\text { het air }}{\longrightarrow}\) \(\mathrm{FeCl}_{2} \stackrel{\mathrm{Zn}}{\longrightarrow} \mathrm{Fe}\) (b) \(\mathrm{Fe} \stackrel{\mathrm{O}_{3} \mathrm{haat}}{\longrightarrow} \mathrm{FeCl}_{3} \stackrel{\mathrm{CO}, 600^{\circ} \mathrm{C}}{\longrightarrow} \mathrm{FeO}\) \(\stackrel{\cos w^{2} \mathrm{C}}{\longrightarrow} \mathrm{Fe}\)c) \(\mathrm{Fe} \stackrel{\mathrm{d} \mathrm{H}_{\mathrm{H}} \mathrm{SO}_{4}}{\longrightarrow} \mathrm{FeSO}_{4} \stackrel{\mathrm{H}, \mathrm{So}_{4}, \mathrm{O}_{3}}{\longrightarrow}\) \(\mathrm{Fe}_{2}\left(\mathrm{SO}_{4}\right)_{2} \stackrel{\text { Heat }}{\longrightarrow} \mathrm{Fe}\) d) \(\mathrm{Fe} \stackrel{\mathrm{O}_{\mathrm{b} \mathrm{ben}}}{\longrightarrow} \mathrm{FeSO}_{4} \stackrel{\mathrm{diH}_{2} \mathrm{So}_{4}}{\longrightarrow}\) \(\mathrm{FeSO}_{4} \stackrel{\text { Heart }}{\longrightarrow} \mathrm{Fe}\)
Problem 179
Which of the following are is best concentrated by froth floatation method? a) Siderite (b) Galena c) Malachite (d) magnetite
Problem 180
Galvanization is applying a coating of? [2016] (a) \(\mathrm{Cu}\) (b) \(\mathrm{Zn}\) (c) \(\overline{\mathrm{Cr}}\) (d) \(\mathrm{Pb}\)
