1
JEE Main 2019 (Online) 12th January Evening Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
The upper stratosphere consisting of the ozone layer protects us from sun's radiation that falls in the wavelength region of -
A
200-315 nm
B
400-550 nm
C
0.8-1.5 nm
D
600-750 nm
2
JEE Main 2019 (Online) 12th January Evening Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
Given

(i)  C (graphite) + O2(g) $$ \to $$ CO2(g); $$\Delta $$rH$$^\Theta $$ = x kJ mol$$-$$1

(ii)  C(graphite) + $${1 \over 2}$$O2(g) $$ \to $$ CO(g); $$\Delta $$rH$$^\Theta $$ = y kJ mol$$-$$1

(iii)  CO(g) + $${1 \over 2}$$ O2(g) $$ \to $$ CO2(g); $$\Delta $$rH$$^\Theta $$ = z kJ mol$$-$$1

Based on the above thermochemical equations, find out which one of the following algebraic relationships is correct?
A
z = x + y
B
x = y + z
C
x = y – z
D
y = 2z – x
3
JEE Main 2019 (Online) 12th January Evening Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
For a reaction consider the plot of $$\ell $$n k versus 1/T given in the figure. If the rate constant of this reaction at 400 K is 10–5 s–1, then the rate constant at 500 K is –

JEE Main 2019 (Online) 12th January Evening Slot Chemistry - Chemical Kinetics and Nuclear Chemistry Question 170 English
A
10$$-$$4 s$$-$$1
B
4 $$ \times $$ 10$$-$$4 s$$-$$1
C
10$$-$$6 s$$-$$1
D
2 $$ \times $$ 10$$-$$4 s$$-$$1
4
JEE Main 2019 (Online) 12th January Evening Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
The aldehydes which will not form Grignard product with one equivalent Grignard reagents are -

JEE Main 2019 (Online) 12th January Evening Slot Chemistry - Aldehydes, Ketones and Carboxylic Acids Question 231 English
A
B and D
B
C and D
C
B, C and D
D
B and C

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