Answer:
2.5 moles of Al
Explanation:
We'll begin by calculating the number of mole in 127 g of Al₂O₃. This can be obtained as follow:
Mass of Al₂O₃ = 127 g
Molar mass of Al₂O₃ = 101.961 g/mol
Mole of Al₂O₃ =?
Mole = mass / molar mass
Mole of Al₂O₃ = 127 / 101.961
Mole of Al₂O₃ = 1.25 mole
Finally, we shall determine the number of mole of Al that reacted. This can be obtained as follow:
4Al + 3O₂ —> 2Al₂O₃
From the balanced equation above,
4 moles of Al reacted to produce 2 moles of Al₂O₃.
Therefore, Xmol of Al will react to produce 1.25 moles of Al₂O₃ i.e
Xmol of Al = (1.25 × 4)/2
Xmol of Al = 2.5 moles.
Thus, 2.5 moles of Al is needed for the reaction.
For every two AB produced, the reaction requires three A
A sample of air is slowly passed through aqueous Sodium hydroxide and then over heater copper <span>Carbon dioxide and oxygen.</span>
This problem is providing us with the mass equivalent to one troy ounce. Thus, the troy ounces of gold in one short ton of average Nevada ore is required and found to be the 0.103 otz according to the following dimensional analysis.
<h3>Dimensional analysis</h3>
In chemistry, a raft of problems do not always provide an equation in order to be solved yet dimensional analysis can be applied, so as to obtain the desired amount in the required units.
Thus, since this problem asks for try ounces in an average Nevada ore, which has 3.2 grams of gold per short ton of ore, one can solve the following setup in order to obtain the required answer in otz:

Where the short tons are cancelled out as well as the grams, in order to obtain:

Learn more about dimensional analysis: brainly.com/question/10874167