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प्रश्न
Write the formula of the following compound:
Sodium dichromate
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उत्तर
Sodium dichromate - Na2Cr2O7 - `"Na"^(1+)["Cr"_2"O"_7]^(2-)`
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संबंधित प्रश्न
Write the chemical formula of the Calcium oxide.
Fill the following blanks with suitable words :
In a chemical reaction, the sum of the masses of the reactants and the products remains unchanged. This is called ....................
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Molecular formula of water is H2O2
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- its sulphate
- its hydroxide.
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Name the element in the compound and give the formula of the following compound:
Phosphoric acid
Name the element in the compound and give the formula of the following compound:
Acetic acid
Write the formula of the following compound:
Potassium sulphate
Write the formula of the following compound:
Calcium bicarbonate
Write the formula of the following compound:
Aluminium hydroxide
Write the formula of the following compound:
Iron [III] oxide
Write the formula of the following compound:
Iron [III] sulphate
Find the valency of the element which is underlined in the following formula.
- NaCl
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Play a game for writing formula.
Example 1: Make placards with symbols and valencies of the elements separately. Each student should hold two placards, one with the symbol in the right hand and the other with the valency in the left hand. Keeping the symbols in place, students should criss-cross their valencies to form the formula of a compound.
Play a game for writing formula.
Example 2: A low-cost model for writing formulae: Take empty blister packs of medicines. Cut them in groups according to the valency of the element, as shown in the figure. Now, you can make formulae by fixing one type of ion into other.
For example:
The formula for sodium sulphate:
2 sodium ions can be fixed on one sulphate ion.
Hence, the formula will be Na2SO4.
Do it yourself:
Now, write the formula of sodium phosphate.
