How many grams of oxygen are in 10.00x1028 molecules of silicon dioxide?

Answer 1

10.00 X 10^28 = 1.0 X 1^29 ( always use scientific notation in chemistry )

1.0 X 10^29 molecules silicon dioxide (1 mole SiO2/6.022 X 10^23)(2 mole O/1 mole SiO2)(16.0 grams/ 1 mole O)

= 5.3 X 10^6 grams of oxygen

Answer 2

To find the number of moles of silicon dioxide in 10.00x10^28 molecules, divide this number by Avogadro's number (6.022x10^23). Then, multiply the result by the molar mass of silicon dioxide (60.08 g/mol) to find the mass of silicon dioxide. Since silicon dioxide consists of 2 oxygen atoms, you can calculate the mass of oxygen by multiplying the mass of silicon dioxide by the ratio of oxygen's molar mass to the total molar mass of silicon dioxide.