How many moles in 28 grams of UO2?

0.22 moles.

28 divided by 124 = 0.22

There are 0.135moles of UO2 in 28 grams of UO2

Explanation:

The SI base unit for amount of substance is the mole. 1 mole is equal to 1 mole UO2, or 207.03grams.

This is the molar mass of UO2, calculated from the sum of the molar masses of uranium and oxygen.

That is, molar mass of UO2 = molar mass of U + (molar mass of O) 2

=238.03g/mol + (16g/mol) 2

= 238.03g/mol + 32g/mol = 270.03g/mol

Molar mass of UO2 = 270.03g/mol

This implies that 1 mole of UO2 has a mass of 207.03 grams

Number of moles of UO2 = mass of UO2 / molar mass of UO2

Mass of UO2 = 28 grams

Number of moles of UO2 = 28 g / 207.03gmol-1

Number of moles = 0.1352 moles of UO2

Therefore, there are 0.135 moles of UO2 in 28 grams of UO2.