Leaching of gold with dilute aqueous solution of NaCN in presence of oxygen gives complex [A], which on reaction with zinc forms the elemental gold and another complex [B]. [A] and [B], respectively are :
02Easy99×since 2002Q1360
Which of the reaction is suitable for concentrating ore by leaching process ?
03Easy99×since 2002Q1361
The methods NOT involved in concentration of ore are
A. Liquation
B. Leaching
C. Electrolysis
D. Hydraulic washing
E. Froth floatation
Choose the correct answer from the options given below :
04Medium99×since 2002Q1362
Given below are two statements :
Statement I : In froth floatation method of rotating paddle agitates the mixture to drive air out of it.
Statement II : Iron pyrites and generally avoided for extraction of iron due to environmental reasons.
In the light of the above statements, choose the correct answer from the options given below :
05Medium99×since 2002Q1363
Which one of the following is not an example of calcination?
06Easy99×since 2002Q1413
The ore that contains both iron and copper is :
07Medium99×since 2002Q1364
Given below are two statements :
Statement I : In the metallurgy process, sulphide ore is converted to oxide before reduction.
Statement II : Oxide ores in general are easier to reduce.
In the light of the above statements, choose the most appropriate answer from the options given below:
08Easy99×since 2002Q1365
Which of the following is used as a stabilizer during the concentration of sulphide ores?
09Easy99×since 2002Q1366
With respect to an ore, Ellingham diagram helps to predict the feasibility of its.