Cobalt metal is added to steel to improve its resistance to corrosion.Calculate no. of moles in a cobalt contain 5×10^20

I don't know the meaning of

5A----10^20.
"in a cobalt 'what' contain 5A---10^20 'what'"?

To calculate the number of moles in a given amount of a substance, you need to know the molar mass of that substance. The molar mass is the mass of one mole of a substance. In this case, you need to know the molar mass of cobalt to calculate the number of moles.

The molar mass of cobalt (Co) is approximately 58.93 g/mol.

Given that you have 5×10^20 atoms of cobalt, you need to convert this quantity to moles using Avogadro's number, which is 6.022 × 10^23 atoms per mole.

To calculate the number of moles, you can use the following formula:

Number of moles = (Number of atoms) / (Avogadro's number)

Number of moles = 5×10^20 / (6.022 × 10^23)

Now let's calculate:

Number of moles = 0.00829

Therefore, there are approximately 0.00829 moles of cobalt in a sample containing 5×10^20 atoms of cobalt.