General Principles And Processes Of Isolation Of Elements Questions are very important for NEET, JEE as well as AIIMS exam. This is because it has many questions based on isolation of elements like hydrogen, chlorine, bromine and iodine from their respective mixtures. It tests your ability to isolate these elements through tests like vaporization, electrolysis and bulb method.
General Principles And Processes Of Isolation Of Elements Questions (Concentration of Ores)
1. Which of the following ores cannot be concentrated by hydraulic washing?
d) Native ores of silver
2. Which of the following cannot be concentrated by electromagnetic separation?
d) Zinc blende
Answer: Zinc blende
3. Where are the magnetic particles collected in concentration by electromagnetic separation?
a) Below the magnetic roller
b) Above the magnetic roller
c) Away from the magnetic roller
d) On the conveyer belt
Answer: Below the magnetic roller
4. What is the property of necessary for an ore to be concentrated by electrostatic separation?
a) The ore particles should be heavier than the gangue particles
b) The ore particles should be magnetic in nature
c) The ores should conduct electricity
d) It should be a sulphide ore
Answer: The ores should conduct electricity
5. Which of the following are collectors used in the froth floatation process?
b) Pine oil
c) Ethyl xanthate
d) Potassium ethyl xanthates
6. What is the role of the rotating paddle in froth floatation?
a) Enhances wettability of gangue particles
b) Stabilizes the froth
c) Draws in air causing frothing
d) Enhances non-wettability of the ore particles
Answer: Draws in air causing frothing
7. Ores obtained from the Earth’s crust are always pure.
8. Concentration of ores is also known as ore-dressing.
9. Which of the cases is suitable for concentration by hand picking?
a) When either the ore or the impurities are magnetic
b) When the ore particles are heavier than the impurities
c) When the ores are good conductors of electricity
d) When the impurities can be distinguished from the ore by the naked eye
Answer: When the impurities can be distinguished from the ore by the naked eye
10. Which of the following equipment is used for concentration by hydraulic washing?
a) Stamp mill
b) Ball mill
c) Wilfley tables
d) Magnetic roller
Answer: Wilfley tables