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.
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