Advertisements
Advertisements
प्रश्न
Why is it not possible to see an atom even with the most powerful microscope ?
उत्तर
Atoms are the building blocks of nature. They are tiniest particles in nature and optical microscopes cannot magnify the image of such a tiny object, so that becomes visible to us. It is possible to watch an atom under an electron microscope.
APPEARS IN
संबंधित प्रश्न
If bromine atom is available in the form of, say, two isotopes `""_35^79Br (49.7%)" and """_35^81Br (50.3%)`, calculate the average atomic mass of bromine atom.
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?
TRUE \ FALSE
Elements combine in definite proportions to form compounds.
ANSWER IN DETAIL
State the postulates of the Dalton’s atomic theory.
Write the names of `("NH"_4)_2"SO"_4` compounds:
An atom has 13 protons and 14 neutrons.
What is the atomic mass of the atom ?
Define: An Atom:
Fill in the blank
A deficiency of electrons produces a ________ charge.
What are the building blocks of matter ?
Name the unit in which the radius of an atom is usually expressed.
Dalton's atomic theory says that atoms are indivisible. Is this statement still valid ? Give reasons for your answer.
Match the pairs.
| Group 'A' | Group 'B' |
| a. Proton | i. Negatively charged |
| b. Electron | ii. Neutral |
| c. Neutron | iii. Positively charged |
Deduce from the datum provided.
| Datum | To deduce |
| \[\ce{_11^23Na}\] | Neutron number |
| \[\ce{_6^14C}\] | Mass number |
| \[\ce{_17^37 Cl}\] | Proton number |
Draw the electron dot structure of this compound.
State the meaning of the term – (a) atom, (b) molecule, (c) radical – with a suitable example.
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.
Define the following term with an example.
Compound
______ is the smallest particle of an element.
The most abundant type of atom is the universe is ______.
