Find the exact atomic masses of the following elements O, Cl, Si, Na, Ca, Cu, Pb. Round them up to whole numbers

The exact values of the atomic masses of the following elements are equal:
О = 16 g / mol
Cl = 35.5 g / mol
Si = 28 g / mol
Na = 23 g / mol
Ca = 40 g / mol
Cu = 64 g / mol
Pb = 207 g / mol



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