Q18 of 203 Page 172

How many moles are there in 34.5 g of sodium? (Atomic mass of Na = 23 u)

Molar mass of sodium(Na) = 23g

Given Mass of the sodium = 34.5g


As we know that, Number of moles= mass of an element/molar mass of an element


Hence Number of moles = 34.5/23 = 1.5 moles.


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