Answer:
To determine the number of moles of NO2 formed when 54g of N2O5 decomposes we need to use the molar mass of N2O5.
The molar mass of N2O5 is given as 108 g/mol.
First we need to calculate the number of moles of N2O5 using the given mass and molar mass.
Number of moles = Mass / Molar mass
Number of moles = 54 g / 108 g/mol
Number of moles = 0.5 mol
According to the balanced chemical equation for the decomposition of N2O5:
N2O5 → 2NO2
We can see that for every 1 mole of N2O5 2 moles of NO2 are formed.
Therefore if we have 0.5 moles of N2O5 we can multiply it by the ratio of moles of NO2 to moles of N2O5 to determine the number of moles of NO2 formed.
Number of moles of NO2 = 0.5 mol N2O5 × (2 mol NO2 / 1 mol N2O5)
Number of moles of NO2 = 1 mol
Therefore when 54g of N2O5 decomposes 1 mole of NO2 is formed.