Tin (II) fluoride (SnF2) is often added to toothpaste as an ingredient to prevent tooth decay. What is the mass of F in grams and 33.7 g of the compound? Round your answer to three significant digits.

Answer 1

To find the mass of F in grams in 33.7 g of SnF2, we need to find the number of moles of SnF2 and then multiply it by the molar mass of F.

The molar mass of SnF2 is:
1 Sn * (atomic mass of Sn) = 1 * 118.71 g/mol = 118.71 g/mol
2 F * (atomic mass of F) = 2 * 18.998 g/mol = 37.996 g/mol

So the molar mass of SnF2 is 118.71 + 37.996 = 156.706 g/mol.

To find the moles of SnF2 in 33.7 g, we divide the mass by the molar mass:
33.7 g / 156.706 g/mol = 0.215 mol

Since there are 2 moles of F in 1 mole of SnF2, there are 0.215 mol * 2 = 0.43 mol of F in 33.7 g of SnF2.

To find the mass of F in grams, we multiply the moles of F by the molar mass of F:
0.43 mol * 18.998 g/mol = 8.187 g.

Rounded to three significant digits, the mass of F in grams in 33.7 g of SnF2 is 8.19 g.