MCQ
Atomic number of elements represent
  • Number of protons in the nucleus
  • B
    Number of neutrons in the nucleus
  • C
    Number of protons and neutrons in nucleus
  • D
    The valency of an element

Answer

Correct option: A.
Number of protons in the nucleus
a
Atomic number of an element represents the number of protons in the nucleus. It is also equal to the number of electrons in neutral atom. The number of neutrons is equal to the difference between mass number and atomic number.

For example, for ${ }_{17}^{37} Cl$, the atomic number is $17$, the mass number is $37$ , there are $17$ , electrons, $17$ protons and $37-17=20$ neutrons.

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

If we want to study relative arrangement of atoms in a molecule we study
Among the following the weakest one is
The following reaction occurs in the Blast furnance where iron ore is reduced to iron metal $Fe _2 O _{3(s)}+3 CO _{( g )} \rightleftharpoons Fe _{( l )}+3 CO _{2(g)}$ Using the Le chatelier's principle, predict which one of the following will not disturb the equilibrium.
Correct order of strength of $\pi -$ bond $(s)$ are 

$(I)$ $BO_3^{-3} > CO_3^{-2} > NO_3^-$

$(II)$ $ClO_4^-> SO_4^{-2} > PO_4^{-3}$

$(III)$ $BF_3 > BCl_3 > BBr_3$

$(IV)$ $AlCl_3 > BCl_3$

What will be the reduction potential of $Cu$ in aqueous solution with $pH = 12$ ? If $K_{sp}$ of $Cu(OH)_2$ is $1\times10^{-19}$ and $E_{C{u^{ + 2}}/Cu}^o = 0.34\,V$ ............. $\mathrm{V}$
Consider the following data for the given reaction  $2 \mathrm{HI}_{(\mathrm{g})} \rightarrow \mathrm{H}_{2(\mathrm{~g})}+\mathrm{I}_{2(\mathrm{~g})}$ .  The order of the reaction is................
  $1$ $2$ $3$
$\mathrm{HI}\left(\mathrm{mol} \mathrm{L}^{-1}\right)$ $0.005$ $0.01$ $0.02$
Rate $\left(\mathrm{mol} \mathrm{L}^{-1} \mathrm{~s}-1\right)$ $7.5 \times 10^{-4}$ $3.0 \times 10^{-3}$ $1.2 \times 10^{-2}$
Which of the following conditions represents an equilibrium
$C{H_3}CN\xrightarrow{{Na + {C_2}{H_5}OH}}X$  The compound $X$ is
From the ground state electronic configuration of the elements given below, pick up the  one with highest value of second ionization energy
Quantum theory was postulated by :