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प्रश्न
Define – Atom.
उत्तर
An atom is the smallest particle of a chemical element that retains its chemical properties.
APPEARS IN
संबंधित प्रश्न
Why is it not possible to see an atom with naked eyes?
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?
ANSWER IN DETAIL
State the postulates of the Dalton’s atomic theory.
Define:- Molecule
Define:- Radicals
Write the names of the elements present in the:-
Glucose
Write the names of `("NH"_4)_2"SO"_4` compounds:
Fill in the blank:
Atoms are _____
Define: Relative atomic mass
What are orbits or shells ?
Name three non-metals/radicals which have valency -1, -2, and -3.
Who originated the word ‘atom’ ?
State Dalton’s atomic theory.
A certain particle ‘X’ has 17 protons, 18 electrons and 20 neutrons.
Does the particle have an excess of electrons or a deficiency of electrons ?
Fill in the blank
A deficiency of electrons produces a ________ charge.
What value has been given to the mass of this reference atom ?
Find the mass of 2 moles of nitrogen atoms.
Define the following term:
Atom
The electronic structure [configuration] of fluorine can be written as 2, 7. In a similar way give the electronic configuration of aluminium
State true or false. If false, correct the statement.
The basic unit of an element is molecule.
K: Potassium:: C: ______.
Name the sub-atomic particles.
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.
The volume occupied by 4.4 g of CO2 at S.T.P ______
Atoms of different elements having ______ mass numbers, but ______ atomic numbers are called isobars.
Does the solubility of a substance change with temperature? Explain with the help of an example.
A sample of vitamic C is known to contain 2.58 ×1024 oxygen atoms. How many moles of oxygen atoms are present in the sample?
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
An atom of Oxygen (O) and two atoms of hydrogen (H.) combine to form a molecule of ______.
