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प्रश्न
What do you understand by the term mole? How many elementary units are in one mole of a substance?
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उत्तर
"A mole is defined as the amount (mass) of a substance containing elementary particles like atoms, molecules or ions equal to Avogadro's number i .e. 6.023 x 1023.
Or a collect ion of 6.023 x 1023 particles is called mole.
Number of elementary uni ts present in one mole of a substance is 6.023 x 1023.
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संबंधित प्रश्न
Calculate the molar mass of the following substance:
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Consider the following reaction and based on the reaction answer the questions that follow :
\[\ce{(NH4)2Cr2O7 ->[heat] N2(g) + 4H2O(g) + Cr2O3}\]
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(iii) The volume in litres or dm3 of N2evolved at STP.
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Correct the statement, if required.
Under the same conditions of temperature and pressure, equal volumes of all gases contain the same number of atoms.
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| 2. | 4 g of H2 | - | 0.25 moles |
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| 4. | 112 g of N2 | - | 0.5 moles |
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