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. The molar mass of an oxygen molecule in kilogram is 32 kg. Calculate the number of oxygen atoms in 10 kg of oxygen and take Avogadro constant as 
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. How many atoms of hydrogen, sulphur and oxygen are in 2 kg of sulphuric acid? The relative atomic mass of hydrogen is 1, sulphur 32, and oxygen 16.
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. The relative atomic mass of carbon is 12 and that of oxygen is 16.
and atomic mass unit is 
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? The relative atomic mass of sodium is 23 and that of chlorine is 35.
and atomic mass unit is 
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is dissolved in 10 litres of water. How many molecules of salt are in each cubic millimetre of water? The molar mass of table salt in kilogram is 58 kg.
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, the molar mass of oil in kilogram is 282 kg and the diameter of the molecule is 0.8 nm.
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, the relative molecular mass of water is 18, the radius of the Earth is 6400 km and the atomic mass unit is 
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