✓✗The energy of a photon of wavelength 400 nm is (h = 6.626 × 10⁻³⁴ J s, c = 3 × 10⁸ m s⁻¹)

✓✗Which of the following series of transitions in the spectrum of the hydrogen atom falls in the visible region?

✓✗The orbital having 3 angular nodes and 3 total nodes is

✓✗The quantum numbers of the last electron of sodium (Z = 11) are

✓✗If the momentum of a particle is doubled, its de Broglie wavelength becomes

✓✗The bond dissociation energy of Cl₂ is 242 kJ mol⁻¹. The longest wavelength of light that can break a single Cl−Cl bond is about (h = 6.626 × 10⁻³⁴ J s, c = 3 × 10⁸ m s⁻¹, 1 eV = 1.602 × 10⁻¹⁹ J) (N_A = 6.022 × 10²³)

✓✗According to the uncertainty principle, it is impossible to determine simultaneously and exactly the

✓✗Statement I: The 4s orbital is filled before 3d.
Statement II: On ionisation of a transition metal, the 4s electrons are lost before the 3d electrons.

✓✗The neutron was discovered by

✓✗Select the correct statements from the following:
A. Atoms of all elements are composed of two fundamental particles.
B. The mass of an electron is 9.10939 × 10⁻³¹ kg.
C. All the isotopes of a given element show the same chemical properties.
D. Protons and electrons are collectively known as nucleons.
E. Dalton's atomic theory regarded the atom as the ultimate particle of matter.
Choose the correct answer from the options given below:

✓✗The total number of orbitals in the shell with n = 3 is

✓✗The shape of an s orbital is

✓✗Statement I: If the position of an electron is known exactly, its momentum is completely uncertain.
Statement II: The product of the uncertainties in position and momentum can be made zero with better instruments.

✓✗Assertion: The uncertainty principle is not significant for a moving cricket ball.
Reason: The uncertainties it predicts for heavy objects are far smaller than the errors of measurement.

✓✗According to Bohr, the angular momentum of an electron in a stationary orbit is