Advertisements
Advertisements
प्रश्न
Differentiate mass number from atomic number.
Advertisements
उत्तर
| Sr. No. | Atomic number | Mass number |
| 1. | The number of electrons or protons in an atom is called atomic number of that atom. | The number of protons and neutrons present is its nucleus is called mass number of that atom. |
| 2. | It is represented by the letter Z | It is represented by the letter ‘A’. |
| 3. | Example: Helium (He) has 2 protons and two electrons hence its atomic number will be 2. | Example: Sodium (Na) has 11 protons and 12 Neutrons hence its mass number A= 11 + 12 = 23 |
APPEARS IN
संबंधित प्रश्न
What is the significance of atomic numbers in the modern Periodic Table?
Sulphur has an atomic number 16 and a mass of 32.
State the number of protons and neutrons in the nucleus of sulphur. Give a simple diagram to show the arrangement of electrons in an atom of sulphur.
Match the atomic numbers 4,8,10,15 and 19 with the following:
Element which can form trivalent ion
Draw the atomic diagram of the following element showing the distribution of – protons, neutrons and the electrons in the various shell of the atom.
Calcium – \[\ce{^40_20Ca}\]
[The upper number represent the – mass number and the lower number represent the – atomic number e.g. calcium – mass number = 40, atomic number = 20]
The Atomic number of an element is 20. It has ______ valence electrons.
‘Z’ is denoted by ______.
In a neutral atom number of protons is equal to the number of neutrons.
Match the following:
| Column A | Column B | ||
| 1. | Mass of proton | a. | +1 |
| 2. | Mass of electron | b. | -1 |
| 3. | Charge of electron | c. | 9.31 x 10-28g |
| 4. | Charge of proton | d. | 1.67 x 10-24g |
Compare the charge and mass of protons and electrons.
Element ‘P' has electronic configuration 2,8,8,1. The number of chlorine atoms present in the chloride of ‘P’ is ______.
