MCQ
An atom of an element has two electrons in the M shell. Identify its atomic number.
  • A
    10
  • B
    12
  • C
    14
  • D
    15

Answer

  1. 12

Explanation:

For M shell value of n = 3. Thus the electronic configuration is: 2, 8, 2 and atomic number is 12.

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

The energy of the electron at infinite distance from the nucleus in Bohr's Model is taken as
An inorganic compound $(A)$ made of two most occuring elements into the earth crust, having a polymeric tetra-headral network structure. With carbon, compound $(A)$ produces a poisonous gas $(B)$ which is the most stable diatomic molecule. Compounds $(A)$ and $(B)$ will be
Bond-breaking is an _________________process.
The $pH$ of the solution containing $50\, mL$ each of $0.10\, M$ sodium acetate and $0.01\, M$ acetic acid is $.......$

[Given $pK _{ a }$ of $CH _{3} COOH =4.57$ ]

$pK_a$ of a weak acid $(HA)$ and $pK_b$ of a weak base $(BOH)$ are $3.2$ and $3.4,$ respectively. The $pH$ of their salt $(AB)$ solution is
Two radiations having energies $E_1$ and $E_2$ as $15\,eV$ and $45\, eV$ respectively  then the relationship in between $\lambda_1$ and $\lambda_2$ will be
Which of the following relation is correct with respect to first $(I)$ and second $(II)$ ionization potentials of sodium and magnesium
Product $(Q)$ is
PCl5, PCl3 and Cl2 are at equilibrium at 500K in a closed container and their concentrations are 0.8 × 10–3mol L–1, 1.2 × 10–3 mol L–1 and 1.2 × 10–3 mol L–1 respectively. The value of Kc for the reaction $\text{PCl}_5\text{g}\rightleftharpoons\text{PCl}_3\text{(g)}+\text{Cl}_2\text{g}$ will be.
Select the correct statements from the following

$A$. Atoms of all elements are composed of two fundamental particles.

$B$. The mass of the electron is $9.10939 \times 10^{-31} kg$.

$C$. All the isotopes of a given element show same chemical properties:

$D$. Protons and electrons are collectively known as nucleons.

$E$. Dalton's atomic theory, regarded the atom as an ultimate particles of matter Choose the correct answer from the options given below