19,000+ solved questions for JEE Advanced, JEE Mains, NEET & IChO — with answers and expert explanations.
By which of the following processes is an oxide ore reduced to the free metal?
In the froth floatation process for benefaction of the ores, the ore particles float because
Which of the following metals cannot be extracted by the carbon reduction process?
Sulphide ores are generally concentrated by the
In the froth-floatation process, the ore particles float because
Concentration of ores is not done by the
In the froth-floatation process, the sulphide ores are concentrated by mixing the ore with
The metal which mainly occurs as oxide ore in nature is:
The ore of calcium which contains phosphorus is
Silicon is the main constituent of
Wolframite (FeWO4), present as an impurity in cassiterite (SnO2), can be removed by the process of
An element whose electronic configuration is 4s13d10. The possibility of element is
Which of the following statements is correct?
The impurities present in a mineral are called
Chemical leaching is useful in the concentration of:
Heating pyrites to remove sulphur is called
Among the following, the most abundant metal in the earth’s crust is
Out of the following metals that cannot be obtained by electrolysis of the aqueous solution of their salts is
The correct order of the abundance of the elements in earth’s crust is (AIMPT 2011)
Which of the following reactions represents the self- reduction process? (a) (b) (c)
The following reactions take place in the blast furnace in the preparation of impure iron. Identify the reaction pertaining to the formation of the slag. (AIPMT 2011)
Which of the following pairs of metals is purified by van Arkel method? (AIPMT 2011)
The percentage of pyridine (C H N) that forms pyridinium ion (C H N H) in a 0.10 M aqueous pyridine solution ( b K for C H N 1.7 10 ) x is (NEET 2016)
What is the pH of the resulting solution when equal volumes of 0.1 M NaOH and 0.01 M HCl are mixed ? (AIPMT 2015)
At 100C the Kw of water is 55 times its value at 25C. What will be the pH of neutral solution? (log 55 = 1.74) (NEET 2013)