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प्रश्न
Name the particles which revolve around the nucleus.
उत्तर
Electron.
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संबंधित प्रश्न
The average atomic mass of a sample of an element X is 16.2 u. What are the percentages of isotopes `""_8^16X" and """_8^18X` in the sample?
Define:- Molecule
Write the names of `"Na"_3"PO"_4` compounds :
Fill in the blank
An ion with positive charge is called ______
Define: Mass number
What is the maximum number of electrons present in:
1. first shell
2. second shell
3. third shell and
4. fourth shell
Fill in the blank
An excess of electrons produces a ________ charge.
What is the usual symbol for (a) and electron (b) a proton, and (c) a neutron?
What are the building blocks of matter ?
Is it possible to see atoms these days ? Explain your answer.
One nm is equal to :
For the symbols H, D and T, write the subatomic particles (protons, neutrons and electrons) found in each one of them.
How many atoms are there in exactly 12 g of carbon-12 element ? (C = 12 u)
A radical take part – unsplit in a chemical reaction and retains its identity in reactions.
With reference to the radical –
- ammonium
- bisulphate
- carbonate
state the group of atoms present in each radical.
Project.
To have an idea of what atoms are, students can be asked to construct atoms using pipe cleaners (thin metal wires-electron shells), pompoms (balls-different colours for protons and neutrons) and beads (electrons). Students will love and enjoy putting them together and they look great hanging from the ceiling in the classroom.
1 mole of Gold and Silver contain same number of atoms.
Give the salient features of “Modern atomic theory”.
Atomic models have been improved over the years. Arrange the following atomic models in the order of their chronological order
- Rutherford’s atomic model
- Thomson’s atomic model
- Bohr’s atomic model
The ______ are combination of atoms of various elements or the same element.
