1
JEE Main 2018 (Online) 15th April Morning Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
Which of the following is a Lewis acid?
A
PH3
B
B(CH3)3
C
NaH
D
NF3
2
JEE Main 2018 (Online) 15th April Morning Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
For Na+, Mg2+, F- and O2-; the correct order of increasing ionic radii is :
A
O2- < F- < Na+ < Mg2+
B
Na+ < Mg2+ < F- < O2-
C
Mg2+ < Na+ < F- < O2-
D
Mg2+ < O2- < Na+ < F-
3
JEE Main 2018 (Online) 15th April Morning Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
In graphite and diamond, the percentage of p-characters of the hybrid orbitals in hybridisation are respectively :
A
33 and 25
B
33 and 75
C
50 and 75
D
67 and 75
4
JEE Main 2018 (Online) 15th April Morning Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
The correct combination is :
A
[Ni(CN)4]2- $$-$$ tetrahedral ;

[Ni(CO)4] $$-$$ paramagnetic
B
[Ni(Cl)4]2- $$-$$ paramagnetic ;

[Ni(CO)4] $$-$$ tetrahedral
C
[Ni(Cl)4]2- $$-$$ square-planar ;

[Ni(CN)4] 2-$$-$$ paramagnetic
D
[Ni(Cl)4]2- $$-$$ diamagnetic ;

[Ni(CO)4] $$-$$square-planar
JEE Main Papers
2023
2021
EXAM MAP
Medical
NEET
Graduate Aptitude Test in Engineering
GATE CSEGATE ECEGATE EEGATE MEGATE CEGATE PIGATE IN
CBSE
Class 12