1
JEE Main 2023 (Online) 31st January Morning Shift
MCQ (Single Correct Answer)
+4
-1
Change Language

The methods NOT involved in concentration of ore are

A. Liquation

B. Leaching

C. Electrolysis

D. Hydraulic washing

E. Froth floatation

Choose the correct answer from the options given below :

A
A and C only
B
C, D and E only
C
B, D and C only
D
B, D and E only
2
JEE Main 2023 (Online) 30th January Evening Shift
MCQ (Single Correct Answer)
+4
-1
Change Language
Given below are two statements:

Statement I: During Electrolytic refining, the pure metal is made to act as anode and its impure metallic form is used as cathode.

Statement II: During the Hall-Heroult electrolysis process, purified $\mathrm{Al}_{2} \mathrm{O}_{3}$ is mixed with $\mathrm{Na}_{3} \mathrm{AlF}_{6}$ to lower the melting point of the mixture.

In the light of the above statements, choose the most appropriate answer from the options given below:
A
Statement $\mathrm{I}$ is correct but Statement II is incorrect
B
Statement I is incorrect but Statement II is correct
C
Both Statement I and Statement II are incorrect
D
Both Statement I and Statement II are correct
3
JEE Main 2023 (Online) 30th January Morning Shift
MCQ (Single Correct Answer)
+4
-1
Change Language

In the extraction of copper, its sulphide ore is heated in a reverberatory furnace after mixing with silica to:

A
remove $$\mathrm{FeO}$$ as $$\mathrm{FeSiO}_{3}$$
B
remove calcium as $$\mathrm{CaSiO}_{3}$$
C
decrease the temperature needed for roasting of $$\mathrm{Cu}_{2} \mathrm{~S}$$
D
separate $$\mathrm{CuO}$$ as $$\mathrm{CuSiO}_{3}$$
4
JEE Main 2023 (Online) 29th January Evening Shift
MCQ (Single Correct Answer)
+4
-1
Change Language

Given below are two statements :

Statement I : Nickel is being used as the catalyst for producing syn gas and edible fats.

Statement II : Silicon forms both electron rich and electron deficient hydrides.

In the light of the above statements, choose the most appropriate answer from the options given below :

A
Statement I is correct but statement II is incorrect
B
Both the statements I and II are correct
C
Both the statements I and II are incorrect
D
Statement I is incorrect but statement II is correct
JEE Main Subjects
EXAM MAP
Joint Entrance Examination
JEE MainJEE AdvancedWB JEEBITSAT
Medical
NEET
Graduate Aptitude Test in Engineering
GATE CSEGATE ECEGATE EEGATE MEGATE CEGATE PIGATE IN