1
JEE Main 2021 (Online) 20th July Evening Shift
+4
-1
Consider two chemical reactions (A) and (B) that take place during metallurgical process:

(A) $$ZnC{O_{3(s)}}\buildrel \Delta \over \longrightarrow Zn{O_{(s)}} + C{O_{2(g)}}$$

(B) $$2Zn{S_{(s)}} + 3{O_{2(g)}}\buildrel \Delta \over \longrightarrow 2Zn{O_{(s)}} + 2S{O_{2(g)}}$$

The correct option of names given to them respectively is :
A
(A) is calcination and (B) is roasting
B
Both (A) and (B) are producing same product so both are roasting
C
Both (A) and (B) are producing same product so both are calcination
D
(A) is roasting and (B) is calcination
2
JEE Main 2021 (Online) 20th July Morning Shift
+4
-1
Given below are two statements. One is labelled as Assertion A nd the other is labelled as Reason R.

Assertion A : Sharp glass edge becomes smooth on heating it upto its melting point.

Reason R : The viscosity of glass decreases on melting.

Choose the most appropriate answer from the options given below.
A
A is true but R is false
B
Both A and R are true but R is NOT the correct explanation of A.
C
A is false but R is true.
D
Both A and R are true and R is the correct explanation of A.
3
JEE Main 2021 (Online) 20th July Morning Shift
+4
-1
An inorganic Compound 'X' on treatment with concentrated H2SO4 produces brown fumes and gives dark brown ring with FeSO4 in presence of concentrated H2SO4. Also Compound 'X' gives precipitate 'Y', when its solution in dilute HCl is treated with H2S gas. The precipitate 'Y' on treatment with concentrated HNO3 followed by excess of NH4OH further gives deep blue coloured solution, Compound 'X' is :
A
Co(NO3)2
B
Pb(NO2)2
C
Cu(NO3)2
D
Pb(NO3)2
4
JEE Main 2021 (Online) 20th July Morning Shift
+4
-1
The metal that can be purified economically by fractional distillation method is :
A
Fe
B
Zn
C
Cu
D
Ni
JEE Main Subjects
Physics
Mechanics
Electricity
Optics
Modern Physics
Chemistry
Physical Chemistry
Inorganic Chemistry
Organic Chemistry
Mathematics
Algebra
Trigonometry
Coordinate Geometry
Calculus
EXAM MAP
Joint Entrance Examination