Introduction to Atomic Structure

Q. Ratio of specific charge of proton and an alpha particle is
1) 2:1
2) 1:2
3) 1:4
4) 1:1

Q.

Please explain effective nuclear charge

Q.

Who found Electron Proton and Neutron?

Q. The correct value of charge to mass ratio of an electron is:

1. $1.7588\times {10}^{11}$ C/g
2. $1.7588\times {10}^8$ C/g
3. $1.7588\times {10}^8$ C/kg
4. $1.7588\times {10}^9$ C/g

Q.

Lithium has 3 electrons, 4 neutrons and 3 protons. Its mass number is:

1. 3

2. 4

3. 7

4. 1

Q. The increasing order of the e/m ratio for protons, neutrons, electrons and alpha particles is?

Q.

What are the five atomic models?

Q.

Calculate the total mass of 1 mole of electrons.

Q. In an atom, electrons and the nucleus are held together by:

1. Electrostatic force of attraction
2. Electrostatic force of repulsion
3. Electrodynamic force of attraction
4. Electrodynamic force of repulsion

Q.

In NaCl crystal each CL minus ion is surrounded by

a) 4 Na+ ions

B) 6 Na

C) 1 Na

D) 2 Na

Q.

The electric charge on one electron is 1.602 * 10-¹9 C. How much charge is present on 0.1 mole of Cu²+ ions?

Q. The e/m value of a proton is:

1. Greater than e/m value of an electron.
2. Less than e/m value of an electron.
3. Equal to e/m value of an electron
4. Depends on element

Q.

An atom that loses electrons becomes a positively-charged ion called

1. cation

2. anion

3. ion

4. all of these

Q. How many electrons with l=two are there in an atom having atomic number 54?

Q.

What is the mass of a positron?

Q. Positive ions are formed from the neutral atom by the :

1. Increase of nuclear charge
2. Gain of protons
3. Loss of electrons
4. Loss of protons

Q.

A hydrogen atom, initially in the ground state is excited by absorbing a photon of wavelength $980\stackrel{0}{A}$. The radius of the atom in the excited state, in terms of Bohr radius $a_0$, will be: $\left(h_c=12500eV-\stackrel{0}{A}\right)$

1. $9a_0$

2. $25a_0$

3. $4a_0$

4. $16a_0$

Q.

What is the charge and mass of an electron?

Q. A subatomic particle has a -1 relative unit charge and the ratio of charge to mass is $1.758820\times {10}^{11}Ck{g}^{–1}$. Find the absolute mass of the sub-atomic particle in kg.

1. $6.4\times {10}^{-31}kg$
2. $9.1\times {10}^{-31}kg$
3. $9.1\times {10}^{-30}kg$
4. $3.8\times {10}^{-31}kg$

Q. The highest value of e/m ratio of cathode rays will be observed when discharge tube is filled with

1. Nitrogen
2. Oxygen
3. Hydrogen
4. Same in all cases

Q.

What is the significance of atomic models?

Q. Assertion: Chemical reactions involve the rearrangement of atoms.
Reason: Atoms are indestructible and can neither be created nor be destroyed in a chemical reaction.

1. Both the Assertion and the Reason are correct and the reason is the correct explanation of the Assertion
2. The Assertion and the Reason are correct but the reason is not the correct explanation of the Assertion
3. The Assertion is true but the reason is false
4. Both the statements are false

Q.

How will you prove that cathode rays are made up of material particles?

Q. The increasing order (lowest first) for the values of $e/m$ (charge/mass) for electron ($e$), proton ($p$), neutron ($n$) and alpha particle ($\alpha$) is:

1. $e$, $p$, $n$, $\alpha$
2. $n$, $p$, , $e$, $\alpha$
3. $n$, $p$, $\alpha$, $e$
4. $n$, $\alpha$, $p$, $e$

Q.

Deuterium an isotope of hydrogen has two neutrons in its nucleus.

1. True
2. False

Q. Which of the following statements is true for Coulomb's law constant $\left(k\right)$?

1. For air, $k=9\times {10}^9{\text{N m}}^2{\text{C}}^{-2}$
2. $k$ does not depend on the medium
3. It is also called vacuum permittivity
4. It is can't be determined when the medium is nitrogen gas

Q.

A___ is a subatomic particle with no charge and unit mass (Proton, Neutron).

Q. The magnitude of charge is the same for which of the following subatomic particles?

1. Electron and proton
2. Electron and neutron
3. Proton and neutron
4. All of the above

Q.

The nucleus of a hydrogen atom is called

1. Proton

2. Neutron

3. Nucleons

4. Electrons

Q.

In the universe two things which does not contain chemistry