1.) Explain the similarity between Mg(OH)2 and Zn(OH)2 in particular why would any insoluble hydroxide tend to dissolve in an acidic solution?
Are they both bases?
2.) Explain the difference in particular how does Mg^+2 appear to form complex ions with OH^- and NH3? If these complex ions form what would you observe?
Would you observe a solid or precipitate?
I need some help. What do you not understand about these questions? Both are bases and Mg(OH)2 does not form complex ions.
1.) Mg(OH)2 and Zn(OH)2 are both hydroxides of metals. While they have similar chemical structures, they are not considered strong bases because they do not readily dissociate in water to produce hydroxide ions.
Insoluble hydroxides, such as Mg(OH)2 and Zn(OH)2, tend to dissolve in acidic solutions due to the following reason: When an acidic solution is added to these hydroxides, the excess hydrogen ions (H+) from the acid react with the hydroxide ions (OH-) present in the insoluble hydroxides. This reaction results in the formation of water molecules, effectively "consuming" the hydroxide ions. As a result, the concentration of the hydroxide ions decreases, allowing the hydroxide to dissolve.
2.) Magnesium (Mg^2+) can form complex ions with hydroxide (OH-) and ammonia (NH3).
When Mg^2+ forms a complex ion with OH-, it can form the complex ion [Mg(OH)4]^2-. In this complex, one magnesium ion is surrounded by four hydroxide ions due to their coordination with the metal ion.
Similarly, Mg^2+ can also form a complex ion with ammonia (NH3). The complex ion formed is [Mg(NH3)6]^2+. In this complex, one magnesium ion is coordinated with six ammonia molecules.
When these complex ions form, you would observe a clear, colorless solution. No solid or precipitate would be formed.
It is important to note that the formation of complex ions can change the solubility and stability of the metal compounds involved.
1.) The similarity between Mg(OH)2 and Zn(OH)2 is that they are both insoluble hydroxides. Insoluble hydroxides are compounds that do not readily dissolve in water.
When an insoluble hydroxide is added to an acidic solution, it tends to dissolve. This is because of the reaction between the acidic solution and the hydroxide ions (OH-) present in the hydroxide compound. Acids release hydrogen ions (H+) in solution, which can react with the hydroxide ions to form water. The formation of water drives the equilibrium towards dissolution, making the insoluble hydroxide soluble.
In the case of Mg(OH)2 and Zn(OH)2, both compounds are bases because they can accept protons (H+) from the acid. The hydroxide ions in these compounds react with the hydrogen ions from the acid to form water. This results in the compounds dissolving in the acidic solution.
2.) The difference lies in how Mg^+2 forms complex ions with OH^- and NH3. When magnesium ion (Mg^+2) reacts with hydroxide ions (OH^-), it forms the complex ion [Mg(OH)4]^2-. This complex ion consists of one magnesium ion surrounded by four hydroxide ions.
On the other hand, when Mg^+2 reacts with ammonia (NH3), it forms the complex ion [Mg(NH3)6]^2+. In this complex ion, one magnesium ion is surrounded by six ammonia molecules.
If these complex ions were to form, you would observe a clear, colorless solution. This is because the formation of these complex ions leads to the dissociation of the original compound into its constituent ions, which are typically in a dissolved state. Therefore, there would not be a solid or precipitate observed in this case.