helpp chemistry/math help first part!?

[Nessa B]

1.How many potassium ions in 2.00 mol KCl?

2.How many atoms are in the 0.489 mol of mercury within the bulb or a thermometer?
3.A sample has 7.51 x 10 to the 24 power molecules of carbon monoxide, CO. How many moles is this?

4.How many grams of Xe are in a sample that contains 0.087 mol Xe?
5.How many atoms of silver are there in a pure silver chain with a mass of 10.6 g?

6.Ibuprofen has a molar mass of 206.31 g/mol. How many moles of ibuprofen are there in a bottle that contains 145 g of ibuprofen?

7. Antimony has two isotopes. The first, amounting to 57.3%, has a mass of 120.9038 amu. The second, amounting to 42.7%, has a mass of 122.9041 amu. What is the average atomic mass of antimony?

8. Find the molar mass of YBa2Cu3O7.

9. An oxide of phosphorus is 56.34% phosphorus, and the rest is oxygen. Calculate the empirical formula for this compound.

10. Determine the empirical formula for a compound made up of 52.11% carbon, 13.14% hydrogen and 34.75% oxyge