Structure of atom practice · Medium

Amongst the following statements, select the set having statements which was proposed by Dalton.
(1) All the atoms of a given element have identical properties including identical mass. Atoms of different elements differ in mass.
(2) When gases combine or reproduced in a chemical reaction they do so in a simple ratio by volume provided all gases are at the same $\mathrm{T} \,\&\, \mathrm{P}$
(3) Chemical reactions involve reorganization of atoms. These are neither created nor destroyed in a chemical reaction.
(4) Matter consists of indivisible atoms

Assertion: The configuration of $Be$-atom cannot be $1 s^2 3 s^2$.
Reason: The electrons enter the various orbitals in the order of increasing energy.

Statement (S): Monochromatic X-rays fall on lighter elements such as carbon and show scattering under the name of Compton effect.

Explanation (E): $\lambda_{\text {scattered }}$ light is always lower than $\lambda_{\text {incident }}$ light.

Sodium exists in two isotopic forms ${Na}^{23}$ and ${Na}^{24}$ in nature. If ${Na}^{24}$ is present at the abundance of $25 \%$ in the nature. The average atomic mass of the element is :-

Which of the following gave the idea of nucleus of the atom?

The momentum of a particle which has a de-Broglie wavelength of $0.1 \mathrm{~nm}$ is

The energy of the electron in the second and the third Bohr's orbits of the hydrogen atom is $-5.42 \times 10^{-12}$ erg and $-2.41 \times 10^{-12}$ erg respectively. Calculate the wavelength of the emitted radiation when the electron drops from the third to the second orbit.

The electronic transition from $n=2$ to $n=1$ will produce the shortest wavelength in (where, $n=$ principal quantum number)

According to the Bohr theory, which of the following transitions in the Hydrogen atom will give rise to the least energetic photon

The number of nodal planes ' $5 d$ ' orbital has is

The wave function ( $\Psi$ ) of 2 s is given by $\Psi_{2 s}=\frac{1}{2 \sqrt{2 \pi}}\left(\frac{1}{a_0}\right)^{1 / 2}\left(2-\frac{r}{a_0}\right) e^{-f / 2 a_0}$

At $r=r_0$, radial node is formed. Thus, $r_0$ in terms of $a_o$

The $\mathrm{\lambda }$ for ${H_\alpha }$ line of Balmer series is  6500 Å. Thus $\mathrm{\lambda }$ for ${H_\beta }$ line of Balmer series is :

Consider the element $Mg,\,\,\,AI,\,\,\,S,\,\,P$ and $Si,$ the correct increasing order of their first ionisation enthalpy is

The ionisation energy of hydrogen atom is 13.6 eV. What will be the ionisation energy of $\mathrm{H}{\mathrm{e}^ + }$?

The total values of magnetic quantum number of an electron when the value of n=2 is:

The frequency of radiation absorbed or emitted when transition occurs between two stationary states with energies $E_1$ (lower) and $E_2$ (higher) is given by

$\alpha$-particles can be detected by using

Electrons and nucleus are held together by

If ${r_1}$ is the radius of the first orbit, the radius of ${n^{th}}$ orbit of H-atom is given by

Correct energy value order is

As the orbit number increases, the difference in two consecutive energy levels

The $\mathrm{K}$ and $\mathrm{L}$ shell of an element are completely filled and there are 16 electrons in M-shell and 2 electrons in $\mathrm{N}$-shell. The atomic number of the element is

Maximum number of electrons which can be accommodated in a g-subshell is:

Yellow light emitted from a sodium lamp has a wavelength $(\lambda)$ of $580 \mathrm{~nm}$. Calculate the frequency (v) and wave number ( $\bar{v})$ of the yellow light.

Highest energy will be absorbed to eject out the electron in the
configuration.

How fast is an electron moving if it has a wavelength equal to the distance it travels in one second? 

The wave function of an electron in the lowest energy state of a hydrogen atom is proportional to $e^{-r / a_0}$, where $r$ is the distance of the electron from the nucleus. Probability is maximum when electron is at

The study of photoelectric effect is useful in understanding :

The energy of an electron in the ground state $(n=1)$ for ${He}^{+}$ ion is $-x \mathrm{~J},$ then that for an electron in $n=2$ state for ${Be}^{3+}$ ion in $\mathrm{J}$ is

For the same electronic transition in the following atom or ion, the frequency of the emitted radiation will be maximum for