Bohr's Model of an Atom

Q.

According to Bohr's model of the atom, electrons radiate energy while revolving in discrete orbits.

1. True

2. False

Q. In the formula, $2n^2$ for finding the maximum number of electrons in an orbit, what does the 'n' represent?

1. The orbit's or shell's serial number
2. Number of electrons in the atom
3. Mass number of the element
4. Atomic number of the element

Q.

Explain: The whole mass of an atom is present in the center of the atom.

Q.

What is/are the postulates of the modern atomic theory?

1. Atoms are indivisible

2. An atom can be created and destroyed by Fusion or Fission.

3. Laws of chemical combination may not always be followed

4. Atoms of an element are all alike

Q.

The extranuclear part of the atom in which electrons are revolving is known as_____.

Q. The number of protons present in an atom is known as its:

1. Mass number
2. Valency
3. Atomic mass
4. Atomic number

Q. Describe Bohr’s stable orbit atomic model.

Q. In Niels Bohr model of the atom, the orbits or shells are represented by letters and numbers. Identify the correct statement.

1. The letters are A, B, C, D.
2. The letters are K, L, M, N.
3. The letters are P, Q, R, S
4. The letters are W, X, Y, Z

Q. Electrons in an atom occupy stationary orbits of fixed energy at different distances from the nucleus was proposed by:

1. J.J. Thomson
2. Sommerfeld
3. Niels Bohr
4. Albert Einstein

Q. In the formula, $2n^2$ for finding the maximum number of electrons in an orbit, what does 'n' represent?

1. Number of electrons
2. Mass number
3. Atomic number
4. The orbit or shell number

Q.

Electrons lose energy of its own while revolving around the nucleus.

1. True
2. False

Q.

According to Bohr's model of the atom, 'while revolving in discrete orbits the electrons do radiate energy.'

1. False

2. True

Q.

Bohr's Model of the atom included idea(s) like:

1. Electrons in atom stay in orbits

2. The electrons can only revolve in certain orbits at certain distance from the nucleus

3. When electrons gain or lose energy they jump from one orbit to another

4. Most of the atom is empty.

Q.

In the formula, $2n^2$ for finding the maximum number of electrons in an orbit, n represents ____.

1. the number of electrons

2. the orbit's or shell's serial number

3. the mass number

4. the atomic number

Q.

Bohrs atomic model assumes circular orbits of the electrons.

1. True
2. False

Q. The energy associated with each orbit as we move away from the nucleus.

1. decreases
2. increases
3. remains the same

Q. Concept of stationary orbit was introduced by :

1. Bohr
2. Rutherford
3. Sommerfeld
4. Thomson

Q.

In Bohr's model of the atom, the orbits or shells are represented by the letters and numbers. Identify the correct statement.

1. The letters are W, X, Y, Z

2. The letters are A, B, C, D.

3. The letters are K, L, M, N.

4. The letters are P, Q, R, S

Q. What are the drawbacks of Bohr's atomic model?

Q. Write three significant features of Bohrs Model of atom.

Q. Elliptical model of atoms is proposed by:

1. Sommer Field
2. None of these
3. Both (a) and (b) above
4. Ruther Ford

Q.

what is quantisation of energy?

Q. An element X has atomic number 94 and mass number 242 emits two alpha particle.What will be the atomic number and mass number of new element formed?

Q. Using Bohr atom model, show that the radius of the first three orbits in

hydrogen atom are in the ratio 1 :4:9.

Q.

Which of the following is correct about Bohr's Atomic model?

1. Electrons revolving around the nucleus are confined to a fixed orbit called shell

2. Electron loses or gains energy while revolving around the nucleus

3. Orbit has their own energy level

4. None of these

Q. What were the drawbacks of Rutherford's model of an atom?

Q.

which of d statement does not form part of bohrs model of hydrogen ato m 1)energy of electrons in orbit is quantised 2)electron in orbit nearest d nucleus has lowest energy 3)electro n revolve in dffrn orbits around nucleus 4)position n velocity of electrons in orbit cnnt be determined simultaneously

Q. Homi Bhabha suggested the name for the Yukawa particle. The particle is _____________.

1. Bosons
2. Mesons
3. Leptons
4. Hardons