1. Find the molar mass of PbO2:
* Lead (Pb) has a molar mass of 207.2 g/mol
* Oxygen (O) has a molar mass of 16.00 g/mol
* PbO2 has one Pb atom and two O atoms: (207.2 g/mol) + (2 * 16.00 g/mol) = 239.2 g/mol
2. Convert kg to grams:
* 1 kg = 1000 g
* 7.44 x 10^4 kg * 1000 g/kg = 7.44 x 10^7 g
3. Calculate the number of moles:
* moles = mass (g) / molar mass (g/mol)
* moles = (7.44 x 10^7 g) / (239.2 g/mol)
* moles = 3.11 x 10^5 mol
Therefore, there are 3.11 x 10^5 moles in 7.44 x 10^4 kg of lead(IV) oxide.
