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प्रश्न
The basic unit of matter is ______.
पर्याय
element
atom
molecule
electron
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उत्तर
The basic unit of matter is atom.
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संबंधित प्रश्न
Write the names of the elements present in the:-
Sodium hydroxide
What are orbits or shells ?
Name three non-metals/radicals which have valency -1, -2, and -3.
An atom has 13 protons and 14 neutrons.
What is the atomic number of the atom ?
Fill in the blank
If an atom loses an electron, it acquires ______ a charge.
What is the usual symbol for (a) and electron (b) a proton, and (c) a neutron?
Is it possible to see atoms these days ? Explain your answer.
What is an atom ? How do atoms usually exist ?
An atom of an element X may be written as `""_9^4"X"`
(a) What does the figure 9 indicate?
(b) What does the figure 4 indicate?
(c) What is the number of protons in atom X?
(d) What is the number of neutrons in atom X?
(e) What is the number of electrons in atom X?
(f) How many electrons are there in the outermost shell of an atom of element X?
(g) Write the symbol of ion formed by an atom of element X.
Match the pairs.
| Group 'A' | Group 'B' |
| a. Proton | i. Negatively charged |
| b. Electron | ii. Neutral |
| c. Neutron | iii. Positively charged |
Elements X and Y have 1 and 7 electrons in their outermost shell respectively.
What will be the charge present of the molecule XY after chemical combination?
State the meaning of the term – (a) atom, (b) molecule, (c) radical – with a suitable example.
State true or false. If false, correct the statement.
An atom is electrically neutral.
Define the following term with an example.
Compound
Atoms of different elements having ______ mass numbers, but ______ atomic numbers are called isobars.
The number of atoms present in a molecule is called its ______.
1 mole of Gold and Silver contain same number of atoms.
Give the salient features of “Modern atomic theory”.
Dalton’s atomic theory successfully explained
(i) Law of conservation of mass
(ii) Law of constant composition
(iii) Law of radioactivity
(iv) Law of multiple proportions
