1
JEE Main 2019 (Online) 10th January Evening Slot
MCQ (Single Correct Answer)
+4
-1
The electrolytes usually used in the electroplating of gold and silver, respectively are:
A
[Au(CN)2] and [Ag(CN)2]
B
[Au(CN)2] and [Ag(Cl)2]
C
[Au(OH)4] and [Ag(OH)2]
D
[Au(NH3)2] and [Ag(CN)2]
2
JEE Main 2019 (Online) 9th January Evening Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
The correct statement regarding the given Ellingham diagram is :

JEE Main 2019 (Online) 9th January Evening Slot Chemistry - Isolation of Elements Question 94 English
A
At 1400oC, Al can be used for the extraction of Zn from ZnO
B
At 500oC, coke can be used for the extraction of Zn from ZnO
C
Coke cannot be used for the extraction of Cu from Cu2O.
D
At 800oC, Cu can be used for the extraction of Zn from ZnO.
3
JEE Main 2019 (Online) 9th January Morning Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
The ore that contains both iron and copper is :
A
Copper Pyrites
B
Malachite
C
Dolomite
D
Azurite
4
JEE Main 2018 (Online) 16th April Morning Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
In the extraction of copper from its sulphate ore, metal is finally obtained by the oxidation of cuprous sulphide with :
A
Fe2O3
B
Cu2O
C
SO2
D
CO
JEE Main Subjects
EXAM MAP
Joint Entrance Examination
JEE MainJEE AdvancedWB JEE
Graduate Aptitude Test in Engineering
GATE CSEGATE ECEGATE EEGATE MEGATE CEGATE PIGATE IN
Medical
NEET