MCQ
For which of the following, the radius will same as for hydrogen atom having $n = 1$
  • A
    $He^+, n = 2$
  • B
    $Li^{+2}, n = 2$
  • $Be^{+3}, n = 2$
  • D
    $Li^{+2}, n = 3$

Answer

Correct option: C.
$Be^{+3}, n = 2$
c
${r_2},B{e^{ + 3}} = \frac{{{r_1}H}}{4} \times {\left( 2 \right)^2}$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

A solution of two components containing $n_{1}$ moles of the $1^{\text {st }}$ component and $n_{2}$ moles of the $2^{\text {nd }}$ component is prepared. $M _{1}$ and $M _{2}$ are the molecular weights of component $1$ and $2$ respectively. If $d$ is the density of the solution in $g\, mL ^{-1}, C _{2}$ is the molarity and $x _{2}$ is the mole fraction of the $2^{\text {nd }}$ component, then $C_{2}$ can be expressed as 

 

A weak acid, $HA$ is found to be $10\%$ ionized in $0.01\, M$ aqueous solution. Calculate the $pH$ of a solution which is $0.1\, M$ in $HA$ and $0.05\, M$ in $NaA.$
Oxidation state of $"S"$ in Peroxodisulphuric acid and Sodium tetrathionate are
$IUPAC$ name of the structure
Given that
$2C(s) + 2O_2(g) \to 2CO_2(g) ; \Delta H = -787\, kJ$
$H_2(g) + \frac{1}{2} O_2(g) \to H_2O(l) ; \Delta H = -286 \,kJ$
$C_2H_2(g) + 2 \frac{1}{2} O_2(g) \to 2CO_2(g) + H_2O(l)$ ;
$\Delta H = -1301\, kJ$
Heat formation of acetylene is .....$kJ$
Match List $I$ (Fuels) with List $II$ (composition) and select the correct answer using the codes given below the lists

List $I$ (Fuels) List $II$ (Composition)
$A.$ Water gas $i.$ A mixture of $CO$ and $N_2$
$B.$ Producer gas $ii.$ Methane
$C.$ Coal gas $iii.$ A mixture of $CO$ and $H_2$
$D.$ Natural gas $iv.$ A mixture of $CO$, $H_2$, $CH_4$ and $CO_2$

$A\,-\,B\,-\,C\,-\,D$ Respectively

All gases have the same number of moles in the same volume at constant temperature and pressure :
All members of a homologous series differ by a :
Which is not similar characteristic $(s)$ about the electronic configuration of $Be, Mg, Ca$?
The hybrdization of $I{F_7}$ is