Question:
Who discovered protons?
Structure of the Atom
Q 1.
Compare an electron, a proton and a neutron in respect of their relative masses and charges.
Q 2.
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 3.
Fill in the blanks :
Anode rays are also called ___________.
Q 4.
Fill in the blanks :
In the three fundamental sub-atomic particles, _________ are negatively charged, _________ are positively charged and ____________ have no charges.
Q 5.
Who discovered protons?
Q 6.
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 7.
Describe briefly Thomson's model of an atom.
Q 8.
What is the absolute mass and charge of a proton ?
Q 9.
How many times is a proton heavier than an electron ?
Q 10.
On the basis of Rutherford’s model of an atom, which subatomic particle is present in the nucleus of an atom?
Q 11.
What is the maximum number of electrons which can be accommodated in the L shell of an atom
Q 12.
State the number of electrons present in the outermost shell of the atoms of the following elements :
(i) Neon(ii)Chlorine
Q 13.
What is the maximum number of electrons an M shell of the atom can accommodate ?
Q 14.
What is mass number?
Q 15.
Give one use each of the following radioactive isotopes :
(a)Uranium-235 (b) Cobalt-60
Q 16.
If an atom contains one electron and one proton, will it carry any charge or not?
Q 17.
What is ionization energy?
Q 18.
What is a neutron ? State its relative mass and charge.
Q 19.
Fill in the blanks :
Atoms are made up of __________, ___________ and __________.
Q 20.
Fill in the blanks :
The maximum number of electrons that can be accommodated in L-shell are _______.
Q 21.
Write a short note on Nucleus.
Q 22.
Fill in the blanks :
______ are atoms of the same element, which have same number of protons but different mass numbers.
Q 23.
Name the radioactive isotope which is used in the treatment of cancer.
Q 24.
Fill in the blanks :
Atomic number is equal to _____________.
Q 25.
What name is given to those isotopes which have unstable nuclei and emit various types of radiations ?
Q 26.
Who discovered electrons?
Q 27.
What are ?-particles?
Q 28.
What is the maximum number of electrons that can go into the N shell of an atom ?
Q 29.
How does an electron differ from a neutron ?
Q 30.
State one use of radioactive isotopes in medicine.
Q 31.
State one use of radioactive isotopes in industry.
Q 32.
What is Atomic Number? Who coined this term?
Q 33.
Fill in the blanks :
Rutherford's scattering experiment is related to to the size of ____________.
Q 34.
What is the maximum number of electrons which can be accommodated in the K shell of an atom
Q 35.
Name the fundamental particle not present in the nucleus of hydrogen atom
Q 36.
What are canal rays?
Q 37.
What were the important features of atomic model based on Rutherford's scattering experiment?
Q 38.
State the location of electrons, protons and neutrons in an atom.
Q 39.
Fill in the blanks :
The fundamental particle not present in hydrogen atom is __________.
Q 40.
Which shell of an atom can accommodate a maximum of
(a) 8 electrons?
Q 41.
(a) Describe Bohr's model of the atom. How did Neils Bohr explain the stability of atom ?
(b) An element has an atomic number of 11 and its mass number is 23. What is the arrangement of electrons in the shells ? State nuclear composition of an atom of the element.
Q 42.
Give one example of a radioactive isotope which is used as a fuel in the reactors of nuclear power plants.
Q 43.
What name is given to those atoms which contain the same number of protons and electrons but different number of neutrons ?
Q 44.
Complete the following statements :
(a) Magnesium has 2 valence electrons in the......... shell.
(b)The valency of nitrogen in N2 molecule is........
(c)Isotopes have different mass numbers because their nuclei contain different number of........
(d) Some boron atoms have mass number 10 and some have mass number 11. These boron atoms with different mass numbers are called............
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.
What are isobars ? Explain with an example.
Q 47.
(a) What are radioactive isotopes ? Give two examples of radioactive isotopes.
(b)Give any two uses of radioactive isotopes.
(c)An element Z contains two naturally occurring isotopes
Z and
Z. If the average atomic mass of this element be 35.5 u, calculate the percentage of two isotopes.
Q 48.
Who discovered nucleus of an atom?
Q 49.
What are the properties of anode rays?
Q 50.
Who discovered X-Rays?
