Calculate the energy if 48.7 g of al reacts in the following reaction. (al = 26.98 g/mol) fe2o3(s) + 2 al(s) →al2o3(s) + 2fe (s) ∆hrxn = -852 kj.

769 kJ

Explanation:

We know that we will need the balanced equation with masses, molar masses, and enthalpies, so let’s gather all the information in one place.

A_r:                       26.98

                Fe₂O₃ + 2Al ⟶ Al₂O₃ + 2Fe; ΔH_rxn = -852 kJ

Mass/g:                 48.7

1. Calculate the moles of Al

Moles of Al = 48.7 × 1/26.98

Moles of Al = 1.805 mol Al

2. Calculate the energy released

The conversion factor is 852 kJ/2 mol Al

Heat = 1.805 × 852/2

Heat = 769 kJ

the answer is true.

a pan containing water is placed in a positio n where it is exposed to a 10 mile per hour wind. the pan contains a uniform depth of 1.27 cm of water, is quite wide, and has a length of 2.44 m in the wind direction. the water in the pan is at a constant temperature of 15.5 °c.