a. \(n_{Ag}=\dfrac{1,8.10^{25}}{6.10^{23}}=30\left(mol\right)\)
b. \(n_{CO_2}=\dfrac{59,4}{44}=1,35\left(mol\right)\)
c. \(n_{K_2O}=\dfrac{4,2.10^{22}}{6.10^{23}}=0,07\left(mol\right)\)
d. \(n_{CuSO_4}=\dfrac{18.10^{23}}{6.10^{23}}=3\left(mol\right)\)
e. \(n_{SO_2}=\dfrac{10,08}{22,4}=0,45\left(mol\right)\)
g. \(n_{Fe_3O_4}=\dfrac{52,2}{232}=0,225\left(mol\right)\)
h. \(n_{O_2}=\dfrac{6,72}{22,4}-0,3\left(mol\right)\)
i. \(n_{N_2}=\dfrac{13,6}{22,4}\approx0,6\left(mol\right)\)