Final answer:
To find the number of molecules in 5.02 moles of Pb(NO3)2, multiply the number of moles by Avogadro's number, resulting in 30.22 × 1023 molecules of Pb(NO3)2.
Step-by-step explanation:
To calculate the number of molecules in 5.02 moles of Pb(NO3)2, we use Avogadro's number, which is 6.022 × 1023 molecules per mole. Thus, the calculation is as follows:
5.02 moles Pb(NO3)2 × (6.022 × 1023 molecules/mole) = 30.22 × 1023 molecules of Pb(NO3)2.