Final answer:
The number of moles of chromium in 24.61 moles of aluminum dichromate is 12.305 moles.
Step-by-step explanation:
To find the number of moles of chromium in 24.61 moles of aluminum dichromate, Al2(Cr2O7)3, we need to determine the mole ratio between chromium and aluminum dichromate.
From the chemical formula, we can see that there are 2 chromium atoms in 1 unit of aluminum dichromate. Therefore, the number of moles of chromium will be half the number of moles of aluminum dichromate.
Since there are 24.61 moles of aluminum dichromate, there will be 24.61/2 = 12.305 moles of chromium.