(i) Explain how gold ore is leached by cyanide process
(ii) Explain the classification of Inosilicates

Explanation

(a) (i)
(i) Gold is usually found in native state
(ii) The leaching process is intended to concentrate the gold metal.
` 4Au_(s) + 8 NaCN_(aq)^(-) + 2H_(2)O_(aq) + O_(2(g)) to 4 Na [ Au(CN)_(2)]_(aq)^(-) + 4NaOH_(aq)^(-)`
` 2Na[Au(CN)_(2)]+ Zn to Na_(2) [ Zn(CN)_(4)] + 2Au darr`
(iii) In this reaction, Zn acts as a reducing agent ,
(ii) Inosilicates : Silicates which contain 'n' number of silicate units liked by sharing two or more oxygen atoms are called inosilicates
Examples : They are further classified as chain silicates and double chain silicates