Iron is made inactive or passive by:
1. H3PO4
2. conc. HNO3
3. conc. H2SO4
4. dil. HNO3
The inner lining of a blast furnace is made up of:
1. graphite bricks
2. silica bricks
3. fire clay bricks
4. basic bricks
Froth floatation process for the concentration of ores is a practical application of:
1. adsorption
2. absorption
3. coagulation
4. sedimentation
Roasting is generally carried out in case of :
1. Oxide ores
2. Sulphide ores
3. Silicate ores
4. Carbonate ores
Which substance is used as basic refractory material in furnace?
1. Al2O3
2. SiO2
3. CaO
4. Fe2O3
Rutile is an ore of:
1. Ti
2. Zr
3. Mn
4. V
Which is not a mineral?
1. Mica
2. Peat
3. Quartz
4. Felspar
Which element is purified by Zone refining?
1. Ge
2. Ge and Si
3. Si
4. None
Alloy is an example of:
1. gel
2. aerosol
3. solid sol
4. emulsion
The second most common element on the earth is:
1. silicon
2. hydrogen
3. nitrogen
4. oxygen