Download App

2. structure of atom — Chemistry STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 ScienceChemistry2. structure of atom1 Mark
MCQ
Assertion : Angular momentum of an electron in any orbit is given by angular momentum $ = \frac{{nh}}{{2\pi }}$, where $n$ is the principal quantum number.
Reason : The principal quantum number, $n$, can have any integral value.
  • A
    If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
  • ✓
    If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
  • C
    If the Assertion is correct but Reason is incorrect.
  • D
    If both the Assertion and Reason are incorrect.
✓

Answer

Correct option: B.
If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
b
Both assertion and reason are correct. Reason is not the correct explanation of assertion.

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

Explore more

More "M.C.Q (1 Marks)" from 2. structure of atom→2. structure of atom — all question types→Chemistry STD 11 Science question papers→Gujarat Board STD 11 Science question papers→Gujarat Board question paper generator→

Similar questions

Identify the correct order of stability of carbocation
→
Which of the following $C -H$ bond has the least bond dissociation energy?
→
From the following thermochemical equations, find out the heat of ionisation $Z$ for a weak acid $HA$

$HA \to A^-+ H^+$ , $\Delta H = Z$
$H^+ + OH^-\to H_2O$, $\Delta H = X$
$HA + OH^-\to A^-+ H_2O$, $\Delta H = Y$

→
Correct statement is
→
The first and second ionisation enthalpies of a metal are $496$ and $4560 \;\mathrm{kJ} \mathrm{mol}^{-1},$ respectively. How many moles of $\mathrm{HCl}$ and $\mathrm{H}_{2} \mathrm{SO}_{4}$ respectively, will be needed to react completely with $1$ mole of the metal hydroxide?
→
Two possible stereo-structures of $CH_3CHOHCOOH,$ which are optically active, are called
→
Identify the $D$ and $E$ in the following reaction

$\begin{array}{*{20}{c}}
  {C{H_3} - CH - CH - C{H_3}\xleftarrow[{ether}]{{Na}}R\,' - Br\,\xrightarrow{{Mg}}'D'\,\xrightarrow{{{H_2}O}}E} \\ 
  {\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\ 
  {\,\,\,\,\,C{H_3}\,\,\,\,\,C{H_3}\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} 
\end{array}$

→
An aqueous solution ox $X$ is added slowly to an aqueous solution of $Y$ as shown in list $I$. The variation in conductivity of these reactions is given in List $II$. Match List $I$ with List $II$ and select the correct answer using the code given below the lists :

List $I$ List $II$
$P$. $\quad \underset{X}{\left( C _2 H _5\right)_3 N }+\underset{ Y }{ CH _3 COOH }$ $1.$ Conductivity decreases and then increases
$Q.$ $\quad \underset{X}{ KI (0.1 M )}+\underset{ Y }{ AgNO _3(0.01 M )}$ $2.$ Conductivity decreases and then does not change much
$R.$ $\quad \underset{X}{ CH _3 COOH }+\underset{ K }{ KOH }$ $3.$ Conductivity increases and then does not change much
$S$. $\quad \underset{X}{ NaOH }+\underset{Y}{ HI }$ $4.$ Conductivity does not change much and then increases

Codes: $ \quad P \quad Q \quad R \quad S $ 

→
A solution of $\mathrm{H}_2 \mathrm{SO}_4$ is $31.4 \% \mathrm{H}_2 \mathrm{SO}_4$ by mass and has a density of $1.25 \mathrm{~g} / \mathrm{mL}$. The molarity of the $\mathrm{H}_2 \mathrm{SO}_4$ solution is _____________$\quad \mathrm{M}$ (nearest integer)[Given molar mass of $\mathrm{H}_2 \mathrm{SO}_4=98 \mathrm{~g} \mathrm{~mol}^{-1}$ ]
→
Which of the following species contain only  $\pi \,-\,$ bond but exhibit paramagnetic nature ?
→