19,000+ solved questions for JEE Advanced, JEE Mains, NEET & IChO — with answers and expert explanations.
Chemical leaching is useful in the concentration of:
Wolframite (FeWO4), present as an impurity in cassiterite (SnO2), can be removed by the process of
In the froth-floatation process, the sulphide ores are concentrated by mixing the ore with
In the froth-floatation process, the ore particles float because
Sulphide ores are generally concentrated by the
Concentration of ores is not done by the
Silicon is the main constituent of
The ore of calcium which contains phosphorus is
The metal which mainly occurs as oxide ore in nature is:
Among the following, the most abundant metal in the earth’s crust is
The impurities present in a mineral are called
The maximum temperature that can be achieved in blast furnace is: (NEET 2021)
Assertion: All the ores are mineral. Reason: Ores contains metals in combined state
Assertion: Al2O3 is converted into Al by reduction with carbon at high temp. Reason: Carbon has greater affinity for oxygen than aluminium.
Assertion: Lead, tin and bismuth are purified by liquation method. Reason: Lead, tin and bismuth have low m.p. as compared to impurities.
Assertion: Wrought iron is more malleable and ductile than steel. Reason: It contains slightly less percentage of carbon.
Assertion: In the electrolytic reduction of Al2O3, cryolite is used. Reason: Cryolite is an ore of aluminium.
Assertion: CuFeS2 is concentrated by froth floatation method. Reason: CuFeS2 is main ore of copper.
Assertion: Cryolite is used in electrolytic extraction of Al from alumina. Reason: It dissolves alumina.
Assertion: In froth flotation process sodium ethyl xanthate is used as collector. Reason: Sulphide ores are water soluble.
Assertion: Thermite mixture Fe2O3+ Al (powder) is used in the welding. Reason: Al is a good reductant.
Assertion: In the extraction of Ag, complex Na [Ag (CN)2] is reacted with Zn. Reason: Zn is d-block transition metal.
Assertion: Ores are generally converted into oxides, prior to reduction. Reason: Metal oxides can be easily reduced.
Assertion: Extraction of iron metal from iron oxide ore is carried out by heating with coke. Reason: The reaction, Fe O (s) Fe(s)+ O (g) -> is a spontaneous process.
Which of the following statements is correct about [Y]?