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प्रश्न
The molecular formula for elemental sulphur is S8.In a sample of 5.12 g of sulphur:
How many molecules and atoms are present?
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उत्तर
Number atoms 1 mole S8 = (6.02 x 1023) x 8
∴ Number of atoms in 0.02 mole S8 = 0.02 x 8 x (6.02 x 1023)
= 9.632 x 1022
Number of molecules in 0.02 (S8) = 0.02 x 6.02 x 1023
= 1.204 x 1022
संबंधित प्रश्न
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\[\ce{(NH4)2Cr2O7 ->[heat] N2(g) + 4H2O(g) + Cr2O3}\]
Calculate :
(i) The quantity in moles of (NH4)2Cr2O7 if 63 gm of (NH4)2Cr2O7 is heated.
(ii) The quantity in moles of nitrogen formed.
(iii) The volume in litres or dm3 of N2evolved at STP.
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(c) If the number of molecules of hydrogen in the cylinder is X, calculate the number of CO2 molecules in the cylinder with the same conditions of temperature and pressure.
(d) State the law that helped you to arrive at the above result.
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Molar volume
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