Question:
What is a neutron ? State its relative mass and charge.
Answer:
The neutron is a neutral particle found in the nucleus of an atom.the relative mass is 1 u and charhe is 0
Structure of the Atom
Q 1.
What do you think would be the observation if the ?-particle scattering experiment is carried out using a foil of a metal other than gold?
Q 2.
Who discovered protons?
Q 3.
Fill in the blanks :
In the three fundamental sub-atomic particles, _________ are negatively charged, _________ are positively charged and ____________ have no charges.
Q 4.
Describe briefly Thomson's model of an atom.
Q 5.
Write a short note on Nucleus.
Q 6.
Who discovered electrons?
Q 7.
If an atom contains one electron and one proton, will it carry any charge or not?
Q 8.
If A = 23 and Z = 11 for Na atom, how many protons, electrons and neutrons present in Na atom?
Q 9.
Fill in the blanks :
Anode rays are also called ___________.
Q 10.
Fill in the blanks :
Rutherford's scattering experiment is related to to the size of ____________.
Q 11.
Compare an electron, a proton and a neutron in respect of their relative masses and charges.
Q 12.
How many times is a proton heavier than an electron ?
Q 13.
What is mass number?
Q 14.
What is the relationship between an atom containing 11 protons, 11 electrons and 11 neutrons, and another atom containing 11 protons, 11 electrons and 12 neutrons ?
Q 15.
What were the important features of atomic model based on Rutherford's scattering experiment?
Q 16.
What is the maximum number of electrons an M shell of the atom can accommodate ?
Q 17.
What is the maximum number of electrons which can be accommodated in the L shell of an atom
Q 18.
State the number of electrons present in the outermost shell of the atoms of the following elements :
(i) Neon(ii)Chlorine
Q 19.
What is the absolute mass and charge of a proton ?
Q 20.
Give one use each of the following radioactive isotopes :
(a)Uranium-235 (b) Cobalt-60
Q 21.
On the basis of Rutherford’s model of an atom, which subatomic particle is present in the nucleus of an atom?
Q 22.
What is ionization energy?
Q 23.
Fill in the following blanks in respect of an atom of an element :
No.of
protons | No.of
neutrons | Mass number | Atomic
number | No.of
electrons | Valency |
|---|
| 11 | 12 | ........ | ....... | ........ | ......... |
Q 24.
Fill in the blanks :
The maximum number of electrons that can be accommodated in L-shell are _______.
Q 25.
What is a proton ? How does it differ from a neutron ?
Q 26.
Who discovered nucleus of an atom?
Q 27.
Fill in the following blanks
Atomic
number | Mass number | Protons | Neutrons | Electrons | Symbol |
|---|
| 10 | 22 | ....... | ........ | ....... | ........ |
Q 28.
State one use of radioactive isotopes in medicine.
Q 29.
What name is given to the pair of atoms such as
N and
N ?
Q 30.
Fill in the blanks :
The maximum number of electrons that can be accommodated in K-shell are _______.
Q 31.
What name is given to those atoms which contain the same number of protons and electrons but different number of neutrons ?
Q 32.
What is the absolute mass and charge of an electron ?
Q 33.
State the location of electrons, protons and neutrons in an atom.
Q 34.
What is the mass of proton as compared to electron?
Q 35.
Fill in the blanks :
Atoms are made up of __________, ___________ and __________.
Q 36.
Fill in the blanks :
The fundamental particle not present in hydrogen atom is __________.
Q 37.
Fill in the blanks :
_______ are atoms having the same mass number but different atomic numbers.
Q 38.
What is the electronic configuration of a hydrogen atom
Q 39.
(a)What are valence electrons ? Where are valence electrons situated in an atom ?
(b)What is the number of valence electrons in the atoms of an element having atomic number 13 ? Name the Valency shell of this atom.
Q 40.
Who discovered neutrons?
Q 41.
Who is known as 'Father of Nucleus Physics'?
Q 42.
What were the observations of Rutherford's ?-scattering experiment?
Q 43.
Fill in the blanks in the following statements :
(a)The number of protons in the nucleus of an atom is called
(b)The total number of protons and neutrons in the nucleus of an atom is called its.........
(c) An atom has atomic mass number 23 and atomic number 11. The atom has..........electrons.
(d) An atom of an element has 11 protons,11 electrons and 12 neutrons. The atomic mass of the atom is........
(e)If the nucleus of an atom has atomic number 17, mass number 37 and there are 17 electrons outside the nucleus, the number of neutrons in it is.........
(f) Almost all the mass of an atom is concentrated in a small region of space called the.......
(g)Cathode rays are a beam of fast moving.......
(h) The anode rays obtained from hydrogen gas consist of particles called.......
(I)The maximum number of electrons that can be accommodated in L shell is.......
(j) The maximum number of electrons that can go into the M shell is.........
(k)The subatomic particle not present in a hydrogen atom is.....
(L) The electron has................charge, the proton has..........charge, and the neutron has............charge.?
Q 44.
State one use of radioactive isotopes in industry.
Q 45.
Given that the percentage abundance of the isotope
Ne, is 90% and that of the isotope
Ne, is 10%,calculate the average atomic mass of neon.
Q 46.
Complete the following table.
| Particle | Electron | Proton | Neutron |
|---|
| (i) Symbol | __ | __ | __ |
| (ii) Nature | __ | __ | __ |
| (iii) Relative Charge | __ | __ | __ |
| (iv) Absolute Charge | __ | __ | __ |
| (v) Relative Mass | __ | __ | __ |
| (vi) Absolute Mass | __ | __ | __ |
Q 47.
What are the limitations of Rutherford’s model of the atom?
Q 48.
Draw a sketch of Bohr’s model of an atom with three shells.
Q 49.
Fill in the blanks :
The fundamental sub-atomic particle called neutron was discovered by ___________.
Q 50.
Fill in the blanks :
Valency is the __________ _____________ of an atom.
