1
JEE Main 2022 (Online) 24th June Evening Shift
MCQ (Single Correct Answer)
+4
-1
Change Language

At 25$$^\circ$$C and 1 atm pressure, the enthalpies of combustion are as given below :

Substance $${H_2}$$ C (graphite) $${C_2}{H_6}(g)$$
$${{{\Delta _c}{H^\Theta }} \over {kJ\,mo{l^{ - 1}}}}$$ $$ - 286.0$$ $$ - 394.0$$ $$ - 1560.0$$

The enthalpy of formation of ethane is

A
+54.0 kJ mol$$-$$1
B
$$-$$68.0 kJ mol$$-$$1
C
$$-$$86.0 kJ mol$$-$$1
D
+97.0 kJ mol$$-$$1
2
JEE Main 2022 (Online) 24th June Evening Shift
MCQ (Single Correct Answer)
+4
-1
Change Language

For a first order reaction, the time required for completion of 90% reaction is 'x' times the half life of the reaction. The value of 'x' is

(Given : ln 10 = 2.303 and log 2 = 0.3010)

A
1.12
B
2.43
C
3.32
D
33.31
3
JEE Main 2022 (Online) 24th June Evening Shift
MCQ (Single Correct Answer)
+4
-1
Change Language

Metals generally melt at very high temperature. Amongst the following, the metal with the highest melting point will be :

A
Hg
B
Ag
C
Ga
D
Cs
4
JEE Main 2022 (Online) 24th June Evening Shift
MCQ (Single Correct Answer)
+4
-1
Change Language
PCl5 is well known, but NCl5 is not. because,
A
nitrogen is less reactive than phosphorus.
B
nitrogen doesn't have d-orbitals in its valence shell.
C
catenation tendency is weaker in nitrogen than phosphorus.
D
size of phosphorus is larger than nitrogen.
JEE Main Papers
2023
2021
EXAM MAP
Medical
NEETAIIMS
Graduate Aptitude Test in Engineering
GATE CSEGATE ECEGATE EEGATE MEGATE CEGATE PIGATE IN
Civil Services
UPSC Civil Service
Defence
NDA
Staff Selection Commission
SSC CGL Tier I
CBSE
Class 12