How would you know if a salt will produce a neutral, acidic or basic solution? I am quite confused. I know you first break them up into their ions but I don't know what to do next. For example:

NaH2PO4= acidic soln

Mg(HSO4)2= neutral soln

Ca(CN)2= basic soln

NH4F= acidic soln

It depends upon the hydrolysis of the salt.

For anions, such as CN^- in Ca(CN)2, the CN^- is hydrolyzed as follows:
CN^- + HOH ==> HCN + OH^- so the solution is basic because it frees up OH^-. What about Ca^2+. It USUALLY is considered as not hydrolyzing.

NaHPO4 is similar:
HPO4^- + HOH ==> H2PO4^- + OH^-; again OH ion are freed up to make a basic solution while the H2PO4^- is a weak acid.

NH4F is one where both cation and anion hydrolyze to give
NH4^+ + F^- + HOH ==> 2H2O + NH3 + HF
Since both are weak the solution will be acid, basic, or neutral depending which is the stronger. In this HF a stronger acid and NH3 is a base so the solution will be acid.

To determine whether a salt will produce a neutral, acidic, or basic solution, you need to consider the ions formed when the salt dissolves in water. Here's an explanation of the steps involved:

1. Break up the salt into its ions: When a salt dissolves, it dissociates into its constituent ions.

NaH2PO4 breaks down into Na+ and H2PO4- ions.
Mg(HSO4)2 breaks down into Mg2+ and HSO4- ions.
Ca(CN)2 breaks down into Ca2+ and CN- ions.
NH4F breaks down into NH4+ and F- ions.

2. Identify the acidic or basic nature of the ions: Look at the individual ions to determine if they are acidic, basic, or neutral.

In NaH2PO4, the H2PO4- ion is derived from phosphoric acid (H3PO4), which is a weak acid. Therefore, it can donate a proton (H+) to the solution, making it acidic.

In Mg(HSO4)2, the HSO4- ion is derived from sulfuric acid (H2SO4), which is a strong acid. However, because there are two HSO4- ions for every Mg2+ ion, they neutralize each other, resulting in a neutral solution.

In Ca(CN)2, the CN- ion is derived from hydrogen cyanide (HCN), which is a weak acid. It can accept a proton (H+), making the solution basic.

In NH4F, the NH4+ ion is derived from ammonia (NH3), which is a weak base. It can donate a proton (H+) to the solution, making it acidic.

3. Determine the overall effect: The overall effect on the solution's pH is determined by comparing the acidic and basic nature of the ions.

If the salt contains an acidic ion that can donate protons (H+) to the solution, the salt will produce an acidic solution.

If the salt contains a basic ion that can accept protons (H+) from the solution, the salt will produce a basic solution.

If the salt contains ions that have both acidic and basic properties, their relative strengths will determine the overall effect. If the acidic and basic properties neutralize each other, the salt will produce a neutral solution.

Applying these steps to the examples given:
- NaH2PO4 contains an acidic ion (H2PO4-), so it will produce an acidic solution.
- Mg(HSO4)2 contains both acidic (HSO4-) and basic (Mg2+) ions, but their properties neutralize each other, resulting in a neutral solution.
- Ca(CN)2 contains a basic ion (CN-), so it will produce a basic solution.
- NH4F contains an acidic ion (NH4+), so it will produce an acidic solution.

To determine whether a salt will produce a neutral, acidic, or basic solution, you can follow these steps:

1. Break down the salt into its constituent ions:
NaH2PO4 → Na+ + H2PO4-
Mg(HSO4)2 → Mg2+ + 2 HSO4-
Ca(CN)2 → Ca2+ + 2 CN-
NH4F → NH4+ + F-

2. Identify the acidic, basic, or neutral nature of each ion:
- Sodium ion (Na+) and ammonium ion (NH4+) are derived from strong bases (NaOH, NH3), so they are neutral.
- Hydrogen phosphate ion (H2PO4-) is derived from a weak acid (H3PO4), so it is acidic.
- Bisulfate ion (HSO4-) is derived from a strong acid (H2SO4), so it is neutral.
- Cyanide ion (CN-) is derived from a weak acid (HCN), so it is basic.
- Fluoride ion (F-) is derived from a weak acid (HF), so it is acidic.

3. Determine the overall nature of the salt solution using the acidic-basic properties of the constituent ions:
- If the salt contains only neutral ions, it will produce a neutral solution.
- If the salt contains acidic ions, it will produce an acidic solution.
- If the salt contains basic ions, it will produce a basic solution.

Applying this information to the examples you provided:

- NaH2PO4: The presence of H2PO4- makes the solution acidic.
- Mg(HSO4)2: Both Mg2+ and HSO4- ions are neutral, so the solution will be neutral.
- Ca(CN)2: The presence of CN- ions makes the solution basic.
- NH4F: The presence of NH4+ makes the solution acidic.

Therefore, NaH2PO4 produces an acidic solution, Mg(HSO4)2 produces a neutral solution, Ca(CN)2 produces a basic solution, and NH4F produces an acidic solution.