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प्रश्न
State the meaning of the term – (a) atom, (b) molecule, (c) radical – with a suitable example.
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उत्तर
(a) Atom: It is the smallest particle of an element, which is made up of only one kind of atom. Atoms are built up of sub-atomic particles protons, neutrons, and electrons.
Example: O - Oxygen atom, H - Hydrogen atom
(b) Molecule: “The smallest particle of a substance which can exist on its own and retains the physical and chemical properties of the substance is called a molecule.”
Example: O2 - Oxygen molecule, H2O - Water molecule
(c) Radical: A radical is an atom of an element or a group of atoms of different elements that behaves as a single unit with a positive or negative charge on it.
Example: \[\ce{NH^+4}\] - Ammonium radical
APPEARS IN
संबंधित प्रश्न
Tick the most appropriate answer.
Who discovered that radioactive rays are given out by uranium?
- Henri Becquerel
- Marie Curie
- Pierre Curie
- Schmidt
TRUE \ FALSE
Elements having a tendency to accept electrons are called metals
WRITE SHORT ANSWER
What is radioactivity?
ANSWER IN DETAIL
Enlist the features of Bohr’s model of an atom. How did he correct the Rutherford’s model ?
Write the names of the elements present in the:-
Ammonia
Fill in the blank
An ion with positive charge is called ______
What does the word ‘atom’ mean?
Name the particle or particles you would expect to find in :
The nucleus of an atom
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Define the following term:
Atom
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Assertion: An atom is electrically neutral.
Reason: Atoms have equal number of protons and electrons.
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An element is composed of ______ atoms.
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The most abundant type of atom is the universe is ______.
