1
JEE Main 2023 (Online) 30th January Evening Shift
MCQ (Single Correct Answer)
+4
-1
Out of Syllabus
Change Language
Boric acid is solid, whereas $\mathrm{BF}_3$ is gas at room temperature because of :
A
Strong van der Waal's interaction in Boric acid
B
Strong covalent bond in $\mathrm{BF}_{3}$
C
Strong hydrogen bond in Boric acid
D
Strong ionic bond in Boric acid
2
JEE Main 2023 (Online) 30th January Evening Shift
MCQ (Single Correct Answer)
+4
-1
Change Language
The correct order of $\mathrm{pK}_{\mathrm{a}}$ values for the following compounds is:

JEE Main 2023 (Online) 30th January Evening Shift Chemistry - Alcohols, Phenols and Ethers Question 38 English
A
$ \mathrm{a}>\mathrm{b}>\mathrm{c}>\mathrm{d}$
B
$c > a > d > b$
C
$\mathrm{b}>\mathrm{d}>\mathrm{a}>\mathrm{c}$
D
$b > a > d > c$
3
JEE Main 2023 (Online) 30th January Evening Shift
MCQ (Single Correct Answer)
+4
-1
Change Language
$1 \mathrm{~L}, 0.02 \mathrm{M}$ solution of $\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{5} \mathrm{SO}_{4}\right]$ Br is mixed with $1 \mathrm{~L}, 0.02 \mathrm{M}$ solution of $\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{5} \mathrm{Br}\right] \mathrm{SO}_{4}$. The resulting solution is divided into two equal parts $(\mathrm{X})$ and treated with excess of $\mathrm{AgNO}_{3}$ solution and $\mathrm{BaCl}_{2}$ solution respectively as shown below:

$1 \mathrm{~L}$ Solution $(\mathrm{X})+\mathrm{AgNO}_{3}$ solution (excess) $\longrightarrow \mathrm{Y}$

$1 \mathrm{~L}$ Solution $(\mathrm{X})+\mathrm{BaCl}_{2}$ solution (excess) $\longrightarrow \mathrm{Z}$

The number of moles of $\mathrm{Y}$ and $\mathrm{Z}$ respectively are
A
$0 .01,0.01$
B
$0.01,0.02$
C
$0.02,0.01$
D
$0.02,0.02$
4
JEE Main 2023 (Online) 30th January Evening Shift
MCQ (Single Correct Answer)
+4
-1
Change Language
The wave function $(\Psi)$ of $2 \mathrm{~s}$ is given by

$$ \Psi_{2 \mathrm{~s}}=\frac{1}{2 \sqrt{2 \pi}}\left(\frac{1}{a_0}\right)^{1 / 2}\left(2-\frac{r}{a_0}\right) e^{-r / 2 a_0} $$

At $r=r_0$, radial node is formed. Thus, $r_0$ in terms of $a_0$
A
$r_0=a_0$
B
$r_0=4 a_0$
C
$r_0=2 a_0$
D
$r_0=\frac{a_0}{2}$
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