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प्रश्न
What do the symbols, H2, S and O4 mean in the formula H2SO4 ?
उत्तर
In H2SO4, H2 represents two atoms of hydrogen; S represents an atom of sulphur; O4 represents 4 atoms of oxygen where all these atoms are chemically bonded to each other to form a molecule of sulphuric acid i.e., H2SO4.
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संबंधित प्रश्न
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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:
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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.
