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How many molecules of substances B are produced when 29.3 g of substance A reacts? The molar mass of substance A is 23.5 g/mol?

 Task: How many molecules of substances B are produced when 29.3 g of substance A reacts? The molar mass of substance A is 23.5 g/mol?
Solution: 
There is a reaction A →B, one molecule A produce one molecule B. 
We can determine the number of the molecules:


when N – number of molecules, Na – Avogadro constant, n – amount of substance, m – mass of substance, M – molar mass of substance.
 (molecules).
Answer: 7.5∙1023 molecules of substances B.

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