1
JEE Main 2023 (Online) 31st January Evening Shift
MCQ (Single Correct Answer)
+4
-1
Out of Syllabus
Change Language
The Lewis acid character of boron tri halides follows the order :
A
$\mathrm{BI}_{3}>\mathrm{BBr}_{3}>\mathrm{BCl}_{3}>\mathrm{BF}_{3}$
B
$\mathrm{BCl}_{3}>\mathrm{BF}_{3}>\mathrm{BBr}_{3}>\mathrm{BI}_{3}$
C
$\mathrm{BF}_{3}>\mathrm{BCl}_{3}>\mathrm{BBr}_{3}>\mathrm{BI}_{3}$
D
$\mathrm{BBr}_{3}>\mathrm{BI}_{3}>\mathrm{BCl}_{3}>\mathrm{BF}_{3}$
2
JEE Main 2023 (Online) 31st January Evening Shift
MCQ (Single Correct Answer)
+4
-1
Change Language
Evaluate the following statements for their correctness.

A. The elevation in boiling point temperature of water will be same for $0.1 \mathrm{M} \, \mathrm{NaCl}$ and $0.1 \mathrm{M}$ urea.

B. Azeotropic mixtures boil without change in their composition.

C. Osmosis always takes place from hypertonic to hypotonic solution.

D. The density of $32 \% \, \mathrm{H}_{2} \mathrm{SO}_{4}$ solution having molarity $4.09 ~\mathrm{M}$ is approximately $1.26 \mathrm{~g} \mathrm{~mL}^{-1}$

E. A negatively charged sol is obtained when KI solution is added to silver nitrate solution.

Choose the correct answer from the options given below :
A
A, B and D only
B
A and C only
C
B and D only
D
B, D and E only
3
JEE Main 2023 (Online) 31st January Evening Shift
MCQ (Single Correct Answer)
+4
-1
Out of Syllabus
Change Language
Which one of the following statements is incorrect?
A
Cast iron is obtained by melting pig iron with scrap iron and coke using hot air blast.
B
The malleable iron is prepared from cast iron by oxidising impurities in a reverberatory furnace.
C
van Arkel method is used to purify tungsten.
D
Boron and Indium can be purified by zone refining method.
4
JEE Main 2023 (Online) 31st January Evening Shift
MCQ (Single Correct Answer)
+4
-1
Change Language
Arrange the following orbitals in decreasing order of energy.

A. $\mathrm{n}=3, \mathrm{l}=0, \mathrm{~m}=0$

B. $\mathrm{n}=4, \mathrm{l}=0, \mathrm{~m}=0$

C. $\mathrm{n}=3, \mathrm{l}=1, \mathrm{~m}=0$

D. $\mathrm{n}=3, \mathrm{l}=2, \mathrm{~m}=1$

The correct option for the order is :
A
$\mathrm{B}>\mathrm{D}>\mathrm{C}>\mathrm{A}$
B
$\mathrm{A}>\mathrm{C}>\mathrm{B}>\mathrm{D}$
C
$\mathrm{D}>\mathrm{B}>\mathrm{A}>\mathrm{C}$
D
$\mathrm{D}>\mathrm{B}>\mathrm{C}>\mathrm{A}$
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