9) A mixture of 80.0 g of Cr2O3 and 8.00 g of C is used to produce elemental Cr by the reaction below: Cr2O3 + 3 C > 2 Cr + 3 CO
a) What is the theoretical yield of Cr that can be obtained from the reaction mixture?
b) The actual yield is 21.7 g Cr. What is the percent yield for the reaction?

a graduated cylinder.

explanation:

number of molecules / avogadro's number * molecule molecular = mass

explanation:

we define a gram-molecular weight as the mass of one mole of any element or compound. a mole contains avogadro's number of units (molecules) –  

6.022

x

10

23

. so, dividing the number of molecules by avogadro's number gives us the number of moles. multiplying that by the molecular weight gives us the mass. from the periodic table we find the gram-molecular weight of u to be238 and of f to be19. so,  

u

f

6

will have a gram-molecular weight of 352g.