The uranium used for nuclear fuel exists in nature in several minerals. Calculate how many moles of uranium are in 8.00 moles of the following:

1. carnotite, K2 (UO2) 2 (VO4) 2 • 3H2O

2. uranophane, CaU2Si2O11 • 7H2O

3. autunite, Ca (UO2) 2 (PO4) 2 • 10H2O

For calculating the number of moles of uranium, we can count how many atoms of uranium exist in 1 molecule of the given, and multiply this by the given 8.00 moles.

Carnotite contains (UO2) 2, meaning that it has 2 U atoms. Multiplying by 8 gives 16 moles of uranium.

Uranophane contains U2, meaning it has 2 U atoms. Multiplying by 8 gives 16 moles of uranium.

Autunite contains (UO2) 2, meaning it has 2 U atoms. Multiplying by 8 also gives 16 moles of uranium.

Therefore, in 8 moles of all 3 compounds given, there are 16 moles of uranium.