An ore of tin containing $FeCrO_4$ is concentrated by

The method of concentrating the ore which makes use of the difference in density between ore and impurities is called:

The pair of oxides,which can be leached out when powdered bauxite containing certain impurities is digested with a concentrated solution of $NaOH$ at $473-523 \ K$ temperature and $35-36 \ bar$ pressure,are:

The function of potassium ethyl xanthate in the froth floatation process is to make the ore

In the leaching of alumina from bauxite,the ore impurity expected to leach out in the process by reacting with $NaOH$ is:

Which of the following ores is best concentrated by the froth-flotation method?