Evaporation technique is used to separate a compound dissolved in a solvent by vaporizing the solvent and converting it to gaseous state. This leaves behind the solid residue present in the solution after the pure solvent is vaporized. The solvent vapors can be collected and condensed to get pure solvent. But the solid residue cannot be considered pure as it is the left over solid after all the solvent is evaporated. If the solution has some impurities, the solid left over includes all of the impurities. So, we cannot obtain a pure solid in evaporation technique.
Answer:
The mass percent of Al(OH)₃ is 15.3%
Explanation:
The reaction is:
Al(OH)₃ + 3HCl = AlCl₃ + 3H₂O
The excess acid is neutralized with a solution of sodium hidroxide, in the reaction:
NaOH + HCl = NaCl + H₂O
The total moles of HCl is:

From the second titration, the moles of excess of HCl is:

The difference between the total and excess of HCl, it can be know the moles that reacts with the aluminum hydroxide, is:

The ratio between HCl and Al(OH)₃ is 3:1. The MW for aluminum hydroxide is 78 g/mol, thus:

The percentage of Al(OH)₃ is:
%
The matter that has the same composition and properties throughout is called pure chemical substance. So the answer is substance.
Bonding MO's have lower energy than antibonding MO's. The bonding MO's lower energy, even lower than its constituent atomic orbitals, accounts for the stability of a molecule in relation to its individual atoms. However, the sum of energy of the MO's must equal the sum of energy of the AO's.
<h3>What is atomic orbital?</h3>
An atomic orbital is a function in atomic theory and quantum mechanics that describes the location and wave-like behavior of an electron in an atom. This formula can be used to calculate the likelihood of locating any atom's electron in any given location surrounding the nucleus. The phrase atomic orbital can also refer to the actual region or place where the electron is projected to be present given the orbital's mathematical form.
Each orbital in an atom is defined by a set of values of the three quantum numbers n, l, and ml, which correspond to the energy, angular momentum, and an angular momentum vector component of the electron, respectively (magnetic quantum number).
To learn more about atomic orbital visit:
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