Structure of atom practice · Medium

The ratio of the radius of the orbit for the electron orbiting the hydrogen nucleus to that of an electron orbiting a deuterium nucleus is:

Calculate the number of electrons which will together weigh one gram.

According to Bohr's atomic theory, which of the following is correct ?

For an atom or ion having single electron, compare the energies of the following orbitals.

$\mathrm{S}_1=$A spherically symmetrical orbital having two spherical nodes.

$\mathrm{S}_2=$ An orbital which is double dumb-bell and has no radial node.

$\mathrm{S}_3=$ An orbital with orbital angular momentum zero and three radial nodes.

$\mathrm{S}_4=$ An orbital having one planar and one radial node.

Given below are two statements:
Statement I Rutherford’s gold foil experiment cannot explain the line spectrum of hydrogen atom.
Statement II Bohr’s model of hydrogen atom contradicts Heisenberg’s uncertainly principle.
In the light of the above statements, choose the most appropriate answer from the options given below:

What is the difference between two species if one has atomic mass $=14$ and atomic number $=7$ whereas the other has atomic mass $=14$ and atomic number $=6$ ?

When electrons are de-exciting to the ground state from $n$th orbit of hydrogen atoms, 15 spectral lines are formed. The shortest wavelength among these will be

Arrange the following type of radiations in increasing order of frequency.

A. Microwaves

B. Amber light from traffic signal

C. Radiation from FM radio

D. Cosmic rays

E. X – rays

For which of the following element, all of its existing ion $\mathrm{M}^{{x}+}$ will be diamagnetic?

Assertion :- Mass numbers of most of the elements are fractional.

Reason :- Mass numbers are obtained by comparing with the mass number of carbon taken as
12.

The radii of two of the first four Bohr's orbits of the hydrogen atom are in the ratio 1∶4. The energy difference between them may be:

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

$\mathrm{(I)}\,\,\,n = 3,\,\,\,l = 2,\,\,{m_1}\, = - 2$
$\mathrm{(II)}\,\,\,n = 3,\,\,\,l = 1,\,\,\,{m_1} = 0$
$\mathrm{(III)}\,\,\,n = 3,\,\,l = 0,\,\,{m_1} = - 1$
$\mathrm{(IV)}\,\,\,n = 3,\,\,l = 2,\,\,{m_1} = 0$
$\mathrm{(V)}\,\,\,n = 3,\,\,l = 3,\,\,{m_1} = - 2$
Of these question state designation which does not describe an allowed state for an electron in an atom?

Which of the following is not possible for $4 p$ or $3 d$ electrons?

Angular momentum of electron in 3rd stationary orbit of hydrogen atom is

What is the packet of energy called?

The last electron placed in the third (n=3) quantum shell for:

Consider the following pairs of electrons
$\begin{array}{cccccccccccccccccccc} {\mathrm{(A)}\,\,\mathrm{(a)}\,\mathrm{n = 3,}\,\,\mathrm{l = 1,}\,{\mathrm{m}_\mathrm{l}}\mathrm{ = 1,}\,\,{\mathrm{m}_\mathrm{s}}\mathrm{ = + }\frac{\mathrm{1}}{\mathrm{2}}}\\ {\,\,\,\,\,\,\,\,\,\,\,\mathrm{(b)}\,\mathrm{n = 3,}\,\,\mathrm{l = 2,}\,{\mathrm{m}_\mathrm{l}}\mathrm{ = 1,}\,\,{\mathrm{m}_\mathrm{s}}\mathrm{ = + }\frac{\mathrm{1}}{\mathrm{2}}}\\ {\,\mathrm{(B) (a) n = 3,}\,\,\mathrm{l = 2,}\,{\mathrm{m}_\mathrm{l}}\mathrm{ = } - \mathrm{2,}\,\,{\mathrm{m}_\mathrm{s}}\mathrm{ = } - \frac{\mathrm{1}}{\mathrm{2}}}\\ {\,\,\,\,\,\,\,\mathrm{(b) n = 3,}\,\,\mathrm{l = 2,}\,{\mathrm{m}_\mathrm{l}}\mathrm{ = } - 1\mathrm{,}\,\,{\mathrm{m}_\mathrm{s}}\mathrm{ = } - \frac{\mathrm{1}}{\mathrm{2}}}\\ {\mathrm{(C)}\,\mathrm{(a) n = 4,}\,\,\mathrm{l = 2,}\,{\mathrm{m}_\mathrm{l}}\mathrm{ = 2,}\,\,{\mathrm{m}_\mathrm{s}}\mathrm{ = + }\frac{\mathrm{1}}{\mathrm{2}}}\\ {\,\,\,\,\,\,\,\,\mathrm{(b) n = 3,}\,\,\mathrm{l = 2,}\,{\mathrm{m}_\mathrm{l}}\mathrm{ = 2,}\,\,{\mathrm{m}_\mathrm{s}}\mathrm{ = + }\frac{\mathrm{1}}{\mathrm{2}}} \end{array}$
The pairs of electrons present in degenerate orbitals is/are:

In the Balmer series of $\mathrm{H}$-spectrum, successive lines tend towards a limiting value of

The electronic configuration of P in ${\mathrm{H}_3}\mathrm{P}{\mathrm{O}_4}$ is

Statement - I: If a nucleus may undergo positron decay as well as K-capture, the amount of
energy released in positron decay is more than that in K-capture.

Statement - II: The loss in K-capture is equal to the difference in atomic masses of parent
nucleus and the daughter nucleus but in positron decay, additional mass loss equal to the
mass of two electrons also occur.

Total number of electrons having $n + l = 3\,in\,Cr\left( {z = 24} \right)$ atom in its ground state is

A laser used to read CDs emits red light of wavelength 700 nm. How many photons does it emit each second if its power is 1.0 W?

Uncertainty in position of a 0.25g particle is ${10^{ - 5}}m.$ The uncertainty in its velocity will be

$n,\,\,l$ and $m$ values of orbitals A and B are given below.
$\begin{array}{cccccccccccccccccccc} {}&n&l&m \\ {\text{A}}&3&2&0 \\ {\text{B}}&3&1&0 \end{array}$
Which statement about A and B orbitals is incorrect?

a. A has more energy than B

b. A possess electron density along axial direction only

c. B has one angular node and one radial node

d. Probability of finding electron density in B is zero along XZ-plane.

The radiation is emitted when a hydrogen atom goes from a higher energy state to a lower energy state. The wavelength of one line in visible region of atomic spectrum of hydrogen is $6.63 \times 10^{-7} \mathrm{~m}$. Energy difference between the two states is

If ${E_1},{E_2}$ and ${E_3}$ represents kinetic energy of electron, $\alpha -$ particle and proton respectively (having same De Broglie wavelength) then

The electron density of ${d_{xy}}$ orbital in yz plane is

The number of nodal planes ‘d’ orbital has

The wavelength of radiation emitted out in the transition $n=4$ to $n=1$ in $\mathrm{Li}^{2+}$ ion is