If 2.112g of fe2o3 reacts with 0.687g of al, how much pure fe will be produced?

1.452 g

Explanation:

We are given;

Mass of Fe₂O₃ as 2.112 g Mass of Aluminium as 0.687 g

We are required to calculate the mass of Fe produced;

Step 1: Determine the number of moles of each reactant

Moles = Mass ÷ Molar mass

Molar mass of Fe₂O₃ is 159.69 g/mol

Moles of Fe₂O₃ = 2.112 g ÷ 159.69 g/mol

                          = 0.0132 moles

                          = 0.013 moles

Molar mass of Aluminium is 26.98 g/mol

Moles of Al = 0.687 g ÷ 26.98 g/mol

                   = 0.0255 moles

                  = 0.026 moles

Step 2: Determine the rate limiting reactant.

The equation for the reaction is given by;

Fe₂O₃ + 2Al → Al₂O₃ + 2Fe

From the reaction, 0.0255 moles of Al would require 0.026 moles × 2 (0.052 moles) of Fe₂O₃.

On the other hand, 0.013 moles of  Fe₂O₃ would require 0.026 moles of Aluminium

Therefore, Fe₂O₃ is the rate limiting reactant for the reaction.

Step 3: Moles of Fe produced

1 mole of Fe₂O₃ reacts to produce 2 moles of Fe

Therefore; Moles of Fe = Moles of Fe₂O₃ × 2

                                      = 0.013 moles × 2

                                      = 0.026 Moles

Step 4: Mass of Fe produced

Mass = Number of moles × Molar mass

Molar mass of Fe is 55.845 g/mol

Therefore;

Mass of Fe = 0.026 moles × 55.845 g/mol

                  = 1.452 g

Therefore, 1.452 g of Fe were produced.

  remember that hf is only the energy of one photon. not two. not three. one.  1) 5.12 * 10^3 photons  find the energy of one photon, then determine how many photons are needed to reach the sensitivity.  e = hf  = (6.626 * 10^-34 js)(5.95 * 10^19 hz)  = 3.94247 * 10^-14 j per photon  (2.02 * 10^-10 j) / (3.94247 * 10^-14 j/photon) = 5123.69149 photons  round to three sig figs.  2) 5.77 * 10^-17 j  energy of pulse = energy per photon * number of photons  = hfn  = (6.626 * 10^-34 js)(1.66 * 10^13 hz)(5250)  = 5.774559 * 10^-17 j  round to three sig figs.  3) 4.07 * 10^8 kj/mol  10^12 pm = 1 m  c = fλ  f = c/λ  e = hf  = hc/λ  = [(6.626 * 10^-34 js)(3.00 * 10^8 m/s) / (2.94 * 10^-12 m)](1 kj/1000 j)(6.02 * 10^23 photons/mol)  = 40702571.4 kj/mol  round to three sig figs.  4) 9.94 * 10^-1 m  e = hc/λ  λ = hc / e  = (6.626 * 10^-34 js)(3.00 * 10^8 m/s) / (2.00 * 10^-25 j)  = 0.9939 m  round to three sig figs.  5) 9.06 * 10^3 photons  energy of pulse = energy per photon * number of photons  number of photons = energy of pulse / energy per photon  = energy of pulse / (hf)  = (3.87 * 10^-13 j) / [(6.626 * 10^-34 js)(6.45 * 10^16 hz)]  = 9055.23695 photons  round to three sig figs.  6) 2.78 * 10^-15 j  this is problem 1, except in reverse.  sensitivity = minumum number of photons * energy per photon  = (5930)(6.626 * 10^-34 js)(7.077 * 10^14 hz)  = 2.78070758 × 10^-15 j  round to three sig figs.