In early 2013,platinum (195.078 g/mol)was selling for about $1575 per troy ounce (one troy ounce is equal to 31.10 g).How many platinum atoms could you buy for $20.00?

Question

Quizplus · Accepted Answer

To convert troy ounces to grams, we use the conversion factor: 1 troy ounce = 31.10 g.So, 1 troy ounce of platinum = 31.10 g of platinum.To convert grams to moles, we use the molar mass of platinum: 195.078 g/mol.So, 31.10 g of platinum = 31.10 g / 195.078 g/mol = 0.1594 mol of platinum.To convert moles to atoms, we use Avogadro's number: 6.022 x 10^23 atoms/mol.So, 0.1594 mol of platinum = 0.1594 mol x 6.022 x 10^23 atoms/mol = 9.60 x 10^22 atoms of platinum.To find out how many platinum atoms we can buy for $20.00, we divide the number of atoms by the price per troy ounce and multiply by the price per $20.00:9.60 x 10^22 atoms / $1575 per troy ounce x $20.00 = 1.219 x 10^21 atoms.Therefore, the correct answer is A: 1.219 x 10^21 atoms.

In Early 2013,platinum (195 ×\times× 1021 Atoms B)7 ×\times× 1021 Atoms C)7 ×\times×

In Early 2013,platinum (195 $\times$ 10²¹ Atoms
B)7 $\times$ 10²¹ Atoms
C)7 $\times$