Science (English Medium) कक्षा ११ - CBSE Question Bank Solutions for Chemistry

In which of the following compounds the carbon marked with asterisk is expected to have greatest positive charge?

Ionic species are stabilised by the dispersal of charge. Which of the following carboxylate ion is the most stable?

Identify the most stable species in the following set of ions giving reason:

\[\ce{\overset{+}{C}H3, \overset{+}{C}H2Br, \overset{+}{C}HBr2, \overset{+}{C}Br3}\]

Identify the most stable species in the following set of ions giving reason:

\[\ce{\overset{Θ}{C}H3, \overset{Θ}{C}H2Cl, \overset{Θ}{C}HCl2, \overset{Θ}{C}Cl3}\]

Give three points of differences between inductive effect and resonance effect.

What is the maximum number of emission lines when the excited electron of an H atom in n = 6 drops to the ground state?

The energy associated with the first orbit in the hydrogen atom is - 2.18 × 10^-18 J atom^-1. What is the energy associated with the fifth orbit?

Calculate the radius of Bohr’s fifth orbit for hydrogen atom

What is the energy in joules, required to shift the electron of the hydrogen atom from the first Bohr orbit to the fifth Bohr orbit and what is the wavelength of the light emitted when the electron returns to the ground state? The ground state electron energy is –2.18 × 10^–11 ergs.

Explain, giving reasons, which of the following sets of quantum numbers are not possible.

1. n = 0, l = 0, ml = 0, ms = + ½
2. n = 1, l = 0, ml = 0, ms = – ½
3. n = 1, l = 1, ml = 0, ms = + ½
4. n = 2, l = 1, ml = 0, ms = – ½
5. n = 3, l = 3, ml = –3, ms = + ½
6. n = 3, l = 1, ml = 0, ms = + ½

How many electrons in an atom may have the following quantum numbers?

n = 4, `m_s =  -1/2`

How many electrons in an atom may have the following quantum numbers?

n = 3, l = 0

Show that the circumference of the Bohr orbit for the hydrogen atom is an integral multiple of the de Broglie wavelength associated with the electron revolving around the orbit.

Calculate the energy required for the process 

\[\ce{He^+_{(g)} -> He^{2+}_{(g)} + e^-}\]

The ionization energy for the H atom in the ground state is 2.18 ×10^–18 J atom^–1

Lifetimes of the molecules in the excited states are often measured by using pulsed radiation source of duration nearly in the nanosecond range. If the radiation source has a duration of 2 ns and the number of photons emitted during the pulse source is 2.5 × 10¹⁵, calculate the energy of the source.

The longest wavelength doublet absorption transition is observed at 589 and 589.6 nm. Calculate the frequency of each transition and energy difference between two excited states.

If the photon of the wavelength 150 pm strikes an atom and one of its inner bound electrons is ejected out with a velocity of 1.5 × 10⁷ ms^–1, calculate the energy with which it is bound to the nucleus.

If the velocity of the electron in Bohr’s first orbit is 2.19 × 10⁶ ms^-1, calculate the de Broglie wavelength associated with it.

Calculate the volume occupied by 8.8 g of CO₂ at 31.1°C and 1 bar pressure. R = 0.083 bar L K^–1 mol^–1.

According to Bohr’s theory, the angular momentum of an electron in 5th orbit is ______.