Advertisements
Advertisements
प्रश्न
What are the atomic numbers of elements whose outermost electrons is represented by 2p3.
Advertisements
उत्तर
2p3
Completing the electron configuration of the element as
1s2 2s2 2p3.
∴ Number of electrons present in the atom of the element = 2 + 2 + 3 = 7
∴ Atomic number of the element = 7
संबंधित प्रश्न
If number of electrons in an atom is 8 and number of protons is also 8, then
- What is the atomic number of the atom? and
- What is the charge on the atom?
Name the particles which actually determine the mass of an atom.
An element has an atomic number 12. How many electrons will be present in the K, L and M energy shells of its atom?
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.
An atom of an element has two electrons in the M shell.
What is the (a) atomic number (b) number of protons in this element?
What is meant by the 'atomic number of an element'?
The diagram represents an isotope of hydrogen [H]. Answer the following:
Atomic no. = 1
Mass no. = 1
If an isotope of ‘H’ has mass no. = 2, how many electrons does it have.
Draw the structure of the following atoms showing the nucleus containing – protons, neutrons and the orbits with the respective electron:
Carbon [At. no. = 6, Mass no. = 12]
Differentiate between the following term:
Atomic number and mass number
The atomic number of an element is 9, it has 10 neutrons. Find the element from the periodic table. What will be its mass number?
What is common salt? Name the elements present in it. Write the formula of common salt. What are the atomic number and the mass number of the elements? Write the ions in the compound.
Complete the following table.
| Atomic Number | Mass Number | Number of Neutrons | Number of Protons | Number of Electrons | Name of the Element |
| 9 | ______ | 10 | ______ | ______ | ______ |
| 16 | ______ | 16 | ______ | ______ | ______ |
| ______ | 24 | ______ | ______ | 12 | Magnesium |
| ______ | 2 | ______ | 1 | ______ | ______ |
| ______ | 1 | 0 | 1 | 1 | ______ |
______ = No. of protons = No. of the electrons.
Electrons revolve around the nucleus in definite open shells.
K and L shells can accommodate a maximum of 2 and 8 electrons respectively.
State the term for the following:
The amount of substance which contains the same number of units as the number of atoms in carbon-12.
