How many moles are there in 8.50x1024 molecules of sodium sulfate, Na2SO3

14.1 mol

Explanation:

1 mole of a substance contains always the same number of molecules, which is equal to Avogadro number:

Which means that 1 mole of a substance contains molecules.

Therefore, this means that moles of a substance will  containe a number of molecules equal to

In this problem, we know that the substance contains

molecules

Therefore, the number of moles in this substance is:

distance, luminosity, brightness, radius, chemical composition, and temperature

the answer is c. nacl