1
JEE Main 2021 (Online) 27th July Evening Shift
MCQ (Single Correct Answer)
+4
-1
The correct order of first ionisation enthalpy is :
A
Mg < S < Al < P
B
Mg < Al < S < P
C
Al < Mg < S < P
D
Mg < Al < P < S
2
JEE Main 2021 (Online) 25th July Evening Shift
MCQ (Single Correct Answer)
+4
-1
The ionic radii of F$$-$$ and O2$$-$$ respectively are 1.33$$\mathop A\limits^o $$ and 1.4$$\mathop A\limits^o $$, while the covalent radius of N is 0.74$$\mathop A\limits^o $$.

The correct statement for the ionic radius of N3$$-$$ from the following is :
A
It is smaller than F$$-$$ and N
B
It is bigger than O2$$-$$ and F$$-$$
C
It is bigger than F$$-$$ and N, but smaller than of O2$$-$$
D
It is smaller than O2$$-$$ and F$$-$$, but bigger than of N
3
JEE Main 2021 (Online) 25th July Morning Shift
MCQ (Single Correct Answer)
+4
-1
The ionic radii of K+, Na+, Al3+ and Mg2+ are in the order:
A
Na+ < K+ < Mg2+ < Al3+
B
Al3+ < Mg2+ < K+ < Na+
C
Al3+ < Mg2+ < Na+ < K+
D
K+ < Al3+ < Mg2+ < Na+
4
JEE Main 2021 (Online) 22th July Evening Shift
MCQ (Single Correct Answer)
+4
-1
Which one of the following statements for D.I. Mendeleeff, is incorrect?
A
He authored the textbook - Principles of Chemistry
B
At the time, he proposed Periodic Table of elements structure of atom was known.
C
Element with atomic number 101 is named after him.
D
He invented accurate barometer.
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