The answer is probably 3.02x10 to the power of 24.
How I got the answer:
There are 6.02x10 to the power of 23.. atom/particles in one mole.
By using cross-multiplying, I multiplied 6.02x10 to the power of 23 with the 5.03 moles to get the answer of 3.02x10 to the power of 24.