Native silver metal forms a water soluble complex with a dilute aqueous solution of NaCN in the presence of
A water soluble complex of silver with a dilute aqueous solution of NaCN is sodium argentocyanide. In the cyanide process, the native form is crushed and treated with 0.1 – 0.2% solution of NaCN and aerated.
Argentocyanide is soluble. Further metal is recovered from the complex by reduction with zinc.
Metals found in free as well as combined states are
By which of the following processes, the ore is made porous?
Stainless steel has iron and
Thermite process is used in reduction of
Bauxite ore is made up of Al2O3 + SiO2 + TiO2 + Fe2O3. This ore is treated with conc. NaOH solution at 500 K and 35 bar pressure for few hours and filtered when hot. In the filtrate, the species present are
When copper pyrites is roasted in excess of air, a mixture of CuO + FeO is formed. FeO is present as impurities. This can be removed as slag during reduction of CuO. The flux added to form slag is
The temperature of the slag zone in the metallurgy of iron using blast furnace is
The ore that is concentrated by froth floatation process is
Which of the following factors is of no significance for roasting sulphide ores to the oxidexs and not subjecting the sulphide ores to carbon reduction directly?