Calculate the number of moles in 75.0 g of dinitrogen trioxide.

Molar mass of dinitrogen trioxide ( N2O3 ) = 76.01 g/mol
 
1 mole 76.01 g
 ? 75.0 g

Number of moles:

n = m / mm

n = 75.0 / 76.01

n = 0.9867 moles

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