Answer:
A. Interactions between the ions of sodium chloride (solute-solute interactions).
B. Interactions involving dipole-dipole attractions (solvent-solvent interactions).
C. Interactions formed during hydration (solute-solvent interactions).
D. Interactions involving ion-ion attractions (solute-solute interactions).
E. Interactions associated with an exothermic process during the dissolution of sodium chloride (solute-solvent interactions).
F. Interactions between the water molecules (solvent-solvent interactions).
G. Interactions formed between the sodium ions and the oxygen atoms of water molecules (solute-solvent interactions).
Explanation:
The solution process takes place in three distinct steps:
- Step 1 is the <u>separation of solvent molecules.
</u>
- Step 2 entails the <u>separation of solute molecules.</u>
These steps require energy input to break attractive intermolecular forces; therefore, <u>they are endothermic</u>.
- Step 3 refers to the <u>mixing of solvent and solute molecules.</u> This process can be <u>exothermic or endothermic</u>.
If the solute-solvent attraction is stronger than the solvent-solvent attraction and solute-solute attraction, the solution process is favorable, or exothermic (ΔHsoln < 0). If the solute-solvent interaction is weaker than the solvent-solvent and solute-solute interactions, then the solution process is endothermic (ΔHsoln > 0).
In the dissolution of sodium chloride, this process is exothermic.
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.
The lower you go, the more acidic. The higher you go, the more alkaline. Your answer would most likely be 6.
