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प्रश्न
Define the following term with an example.
Element
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उत्तर
Element: It is a substance that cannot be broken down into simpler substance by chemical means
Ex.: Oxygen, Hydrogen, Gold & Helium.
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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.
ANSWER IN DETAIL
Enlist the features of Bohr’s model of an atom. How did he correct the Rutherford’s model ?
Define:- Molecule
Write the names of the elements present in the following compound.
Common salt
Define: Ions
What does an atom consist of ? Explain.
Give two examples for each of ionic and covalent bond.
Fill in the blank
If an atom gains an electron, it is called an _______
Fill in the blank
An excess of electrons produces a ________ charge.
Fill in the following blanks with suitable words :
In water, the proportion of oxygen and hydrogen is .............. by mass.
Define the following term:
Atom
Elements X and Y have 1 and 7 electrons in their outermost shell respectively.
Which element will gain electron?
State true or false. If false, correct the statement.
The basic unit of an element is molecule.
Draw the structure of an atom and explain the position of the sub-atomic particles.
An atom of an element has no electron. Will that atom have any mass or not? Can an atom exist without electron? If so then give example.
Atoms of one element can be transmuted into atoms of other elements by ______
Give the salient features of “Modern atomic theory”.
The graphite refill used is pencil is made of element called ______.
An atom of Oxygen (O) and two atoms of hydrogen (H.) combine to form a molecule of ______.
Lead is also known as plumbum.
