Atomic Structure - Physical Chemistry - Chemistry Previous Year Questions

Two statements are given below :

Statement I : In H atom, the energy of $2 s$ and $2 p$ orbitals is same.

Statements II : In He atom, the energy of $2 s$ and $2 p$ orbitals is same.

The correct answer is

Identify the incorrect statement from the following?

The electron in hydrogen atom undergoes transition from higher orbits to an orbit of radius 476.1 pm . This transition corresponds to which of the following series?

When electromagnetic radiation of wavelength 310 nm falls on the surface of a metal having work function 3.55 eV , the velocity of photoelectrons emitted is $x \times 10^5 \mathrm{~ms}^{-1}$. The value of $x$ is (Nearest integer) $\left(m_e=9 \times 10^{-31} \mathrm{~kg}\right)$

The radius of stationary state $(n=2)$ of hydrogen atom is $x \mathrm{pm}$. The radius of stationary state $(n=3)$ of $\mathrm{He}^{+}$ion (in pm) is

Work functions of four metals $M_1, M_2, M_3$ and $M_4$ are $4.8,4.3,4.75$ and 3.75 eV respectively. The metals which do not show photoelectric effect when light of wavelength 310 nm falls on the metals are

In the atomic spectrum of hydrogen, the wavelengths of the spectral lines corresponding to electronic transitions (i) $n=4$ to $n=2$ and (ii) $n=3$ to $n=1$ are $\lambda_1$ and $\lambda_2 \mathop {\rm{A}}\limits^{\rm{o}}$ respectively. The value of ( $\lambda_1-\lambda_2$ ) (in cm ) is ( $R_{\mathrm{H}}=$ Rydberg constant)

The energy associated with electron in first orbit of hydrogen atom is $-2.18 \times 10^{-18} \mathrm{~J}$. The frequency of the light required (in Hz ) to excite the electron to fifth orbit is ( $h=6.6 \times 10^{-34} \mathrm{Js}$ )

In $\mathrm{Sr}(Z=38)$, the number of electrons with $l=0$ is $x$, number of electrons with $l=2$ is $y \cdot(x-y)$ is equal to ( $l=$ Azimuthal quantum number)

In hydrogen atom, an electron is transferred from an orbit of radius 1.3225 nm to another orbit of radius 0.2116 nm . What is the energy (in J ) of emitted radiation?

Observe the following statements.

Statement -I Rutherford model of an atom cannot explain the stability of an atom.

Statement-II The wavelength of X-rays is higher than the wavelength of microwaves.

The correct answer is

An electromagnetic radiation of wavelength 331.5 nm is made to strike the surface of a metal. Electrons are emitted with a kinetic energy of $12 \times 10^5 \mathrm{~J} \mathrm{~mol}^{-1}$. The work function (in eV ) of the metal is $\left(h=6.63 \times 10^{-34} \mathrm{Js}, N_A=6 \times 10^{23} \mathrm{~mol}^{-1}\right)$

The radius of second orbit of hydrogen atom is same as that of orbit ( $n$ ) of an ion ( $x$ ), $n$ and $x$ are respectively.