Statement I: Leaching of gold with cyanide ion in absence of air / O₂ leads to cyano complex of Au(III)

Statement II: Zinc is oxidized during the displacement reaction carried out for gold extraction.

In the light of the above statements, choose the correct answer form the options given below.

The ${\left(\frac{\partial E}{\partial T}\right)}_P$ of different types of half cells are as follows:

(Where E is the electromotive force )

Which of the above half cells would be preferred to be used as reference electrode

Given are two statements one is labeled as Assertion A and other is labeled as Reason R.

Assertion A : Magnesium can reduce Al₂O₃ at a temperature below 1350°C, while above 1350°C aluminium can reduce MgO

Reason R : The melting and boiling points of magnesium are lower thatn those of aluminium.

In light of the above statements, choose most appropriate answer for the options given below

In metallurgy the term “gangue” is used for:

The processes of calcination and roasting in metallurgical industries, respectively, can lead to:

The correct order of increasing intermolecular hydrogen bond strength is