The decomposition of Al2O3 to form pure aluminum (Al) along with the release of oxygen (O2) gas can be represented by the following chemical reaction:
2Al2O3 → 4Al + 3O2
Based on the reaction stoichiometry:
2 moles of aluminum oxide decomposes to form 4 moles of pure aluminum
Therefore, if 29.0 moles of aluminum is recovered, then the moles of aluminum oxide required will be:
= 29.0 moles Al * 2 moles Al2O3/4 moles Al
= 14.5 moles of Al2O3
The particles in a solid are tightly packed and locked in place. Although we cannot see it or feel it, the particles are vibrating in place.
As these molecules heat up, they will vibrate more vigorously, and will eventually turn to water, then gas.
Answer:
a) Precision
b) Accuracy
c) Accuracy and precision
d) Accuracy
Explanation:
When an experiment is done more than once to determine if the results are statistically ok, two forms of the validations are possible the accuracy and precision. When the values of the various experiments are close to the known value, then they are accurate. When the values are close to each other they are precise. So, sometimes the results are precise but are not accurate, and vice-versa.
a) Here, the person wants to find if the 5 aliquots will have close results, so, he or she is looking for precision.
b) Here the amount of analyte is already known, and the person wants to identify if the value will be the same when analyzed together with another sample, thus he or she is looking for accuracy.
c) Here the three results will be compared with each other (precision) and with the standard value of the method (accuracy).
d) The methods will be tested, and the values will be compared with the standard known value, so the person is looking for accuracy.
Answer:
the chile trench is closer and the tonga is further
Explanation: because
