NEET UG 2002 — Chemistry Inorganic Chemistry

2002mcqmedium

Which of the following order is wrong?

Official previous-year question

Held on 30 Apr 2002 · Verified 9 Jul 2026.

Options

A
$\mathrm{NH}_3 < \mathrm{PH}_3 < \mathrm{AsH}_3$ - Acidic
B
$\mathrm{Li} < \mathrm{Be} < \mathrm{B} < \mathrm{C}-$ First ionization potential
C
$\mathrm{Al}_2 \mathrm{O}_3 < \mathrm{MgO} < \mathrm{Na}_2 \mathrm{O} < \mathrm{K}_2 \mathrm{O}-$ Basic
D
$\mathrm{Li}^{+} < \mathrm{Na}^{+} < \mathrm{K}^{+} < \mathrm{Cs}^{+}-$ Ionic radius

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Solution

$\mathrm{Li}, \mathrm{Be}, \mathrm{B}, \mathrm{C}$ - these elements belong to the same period. Generally, the value of 1 st ionisation potential increases in moving from left to right in a period, since the nuclear charge of the elements also increase in the same direction. But the ionisation potential of boron $\left(\mathrm{B} \rightarrow 2 s^2 p^1\right)$ is lower than that of beryllium (Be $\rightarrow 2 s^2$ ), since in case of boron, $2 p^1$ electron have to be removed to get $\mathrm{B}^{+}$ , while in case of $\mathrm{Be}, 2 s^2$ electron have to be removed to get $\mathrm{Be}^{+}\left(2 s^1\right)$ . $p$ electron can be removed more easily than $s$ electron so the energy required to remove electron will be less in case of boron. The order will be $\mathrm{Li} < \mathrm{B} < \mathrm{Be} < \mathrm{C}$

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NEET UG 2002 — Chemistry Inorganic Chemistry

2002mcqmedium

Which of the following order is wrong?

Official previous-year question

Held on 30 Apr 2002 · Verified 9 Jul 2026.

Options

A
$\mathrm{NH}_3 < \mathrm{PH}_3 < \mathrm{AsH}_3$ - Acidic
B
$\mathrm{Li} < \mathrm{Be} < \mathrm{B} < \mathrm{C}-$ First ionization potential
C
$\mathrm{Al}_2 \mathrm{O}_3 < \mathrm{MgO} < \mathrm{Na}_2 \mathrm{O} < \mathrm{K}_2 \mathrm{O}-$ Basic
D
$\mathrm{Li}^{+} < \mathrm{Na}^{+} < \mathrm{K}^{+} < \mathrm{Cs}^{+}-$ Ionic radius

NEET UG 2002 — Chemistry Inorganic Chemistry

Options

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Solution

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NEET UG 2002 — Chemistry Inorganic Chemistry

Options

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Solution

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NEET UG Inorganic Chemistry in other years

More NEET UG Inorganic Chemistry questions

Other Chemistry topics for NEET UG

Physical Chemistry

Organic Chemistry

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