What is the theoretical yield of chromium that can be produced by the reaction of 40.0 g of cr2o3 with 8.00 g of aluminum according to the chemical equation below? 2al + cr2o3 --> al2o3 + 2cr?

The theoretical yield of chromium will be 15.05 g

Solution:

The balance chemical equation

                                 2Al + Cr2o3 --> Al2o3 + 2Cr

From given mass, we can calculate moles

mass of Al = 8 g                                          mass of Cr2O3 = 40g

Molar mass of Al = 26.98g/mol               Molar mass of Cr2O3 = 151.9g/mol

Mole of Al = 8/26.98                                Mole of Cr2O3 = 40/151.9

Mole of Al = 0.29 mole                            Mole of Cr2O3 = 0.26 mol

Here, we have to find out the limiting reactant (The reactant which will give the least amount of product) so from balance chemical equations

No. of mole of Al =No. of moles of Cr

                        2  =   2

                  0.29  = 2/2 × 0.29 = 0.29 mole

No. of mole of Cr2O3 =No. of moles of Cr

                             1    =    2

                        0.26   =   2/1 × 0.26 = 0.52 mole

So we can say, Al is a limiting reactant so

No. of mole of Al =No. of moles of Cr

                        2  =   2

                  0.29  = 2/2 × 0.29 = 0.29 mole

Moles of Cr = 0.29 mol

Molar mass of Cr = 51.9 g/mol

mass of Cr = 0.29 × 51.9 = 15.05 g

Conclusion:

The calculated mass from balance chemical equation of Cr will be 15.05 g.

each  column  of the  table  is called a group. elements in a group share similar properties. groups are  read  from  top  to  bottom. metal. metalloid. nonmetal. solid. liquid. gas. fe. hg. o.  2. 3. 4. 5. 6. 7. 8. 9.  2. beryllium. 9.012. 4.  sodium. 22.990.  11. 3.  magnesium. 24.305.  12.  potassium. 39.098.  19. 4.  calcium. 40.078.  20. i guess  i