1
JEE Main 2019 (Online) 11th January Evening Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
For the equilibrium,
2H2O $$\rightleftharpoons$$ H3O+ + OH$$-$$, the value of $$\Delta $$Go at 298 K is approximately :
A
$$-$$ 80 kJ mol–1
B
100 kJ mol$$-$$1
C
$$-$$ 100 kJ mol$$-$$1
D
80 kJ mol–1
2
JEE Main 2019 (Online) 11th January Evening Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
The correct match between Item I and Item II is :

Item I Item II
(A) Ester test (P) Tyr
(B) Carbylamine test (Q) Asp
(C) Phthalein dye test
(R) Ser
(S) Lys
A
(A)$$ \to $$(Q); (B)$$ \to $$(S); (C)$$ \to $$(P)
B
(A)$$ \to $$(R); (B)$$ \to $$(S); (C)$$ \to $$(Q)
C
(A)$$ \to $$(R); (B)$$ \to $$(Q); (C)$$ \to $$(P)
D
(A)$$ \to $$(Q); (B)$$ \to $$(S); (C)$$ \to $$(R)
3
JEE Main 2019 (Online) 11th January Evening Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
The correct option with respect to the Pauling electronegativity values of the element is :
A
Ga < Ge
B
Si < Al
C
Te > Se
D
P > S
4
JEE Main 2019 (Online) 11th January Evening Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
The de Broglie wavelength ($$\lambda $$) associated with a photoelectron varies with the frequency (v) of the incident radiation as, [v0 is threshold frequency] :
A
$$\lambda \,\infty \,{1 \over {{{\left( {v - {v_0}} \right)}^{{3 \over 2}}}}}$$
B
$$\lambda \,\infty \,{1 \over {{{\left( {v - {v_0}} \right)}^{{1 \over 4}}}}}$$
C
$$\lambda \,\infty \,{1 \over {\left( {v - {v_0}} \right)}}$$
D
$$\lambda \,\infty \,{1 \over {{{\left( {v - {v_0}} \right)}^{{1 \over 2}}}}}$$

JEE Main Papers

All year-wise previous year question papers

2023
2021