Question 7

[Carla Bruebach 1C]

Can someone explain how to do question 7 on acheive? I'm very confused on how to classify the salts as acidic, basic, or neutral.

[Daniel Li 3C]

Hi,
I think in order to classify a salt as acidic, basic, and neutral, you would need to look at the cation and the anion. If both the cation and anion are from strong acids and strong bases, then the salt would be considered neutral, they cancel out in a sense. If the acid is a strong acid and the base is weak and they combine to form a salt for example, it would be acidic and vice versa. Hope this helps!

[Narin Maisha 2H]

To do this problem you need to identify the anions and cations, and what types of acids and bases they are. If they are made up of a strong acid and weak base, then it would be acidic, and vise versa for basic. If they are made up of a strong base and strong acid then it will be neutral.

[Michael Vigman 2D]

Cations found in strong bases don't hydrolyze (react in water).
Conversely, cations that are the conjugate acids of weak bases will hydrolyze and produce acidic solutions.

Anions found in strong acids don't hydrolyze.
Conversely, anions that are the conjugate bases of weak acids will hydrolyze and produce basic solutions.

If neither the cation or anion can hydrolyze because they are part of strong acids / strong bases, then the solution is neutral.

In order to determine the salts as acidic basic or neutral, follow this procedure!
1. Split up the salt of interest
2. Determine if the cation/anion is from a strong base / strong acid.
3. Sort accordingly, noting that the solution can be neutral if both are from strong base / strong acid.

Here's a list of the strong bases / acids. I've found it is easiest to simply memorize these so then anything that isn't a strong acid / base must be weak.

Strong acids:
HCl, HBr, HI, HClO₄, HNO₃, HIO₄, H₂SO₄, HClO₃

Strong bases:
LiOH, NaOH, KOH, RbOH, CsOH, Ba(OH)₂, Sr(OH)₂, Ca(OH)₂

[Vanessa Wiratmo 3k]

Hello,

In order to do this problem, you will need to look at the components of the salt, meaning the cation and the anion. A salt may be defined as the product of a neutralization reaction of an acid and a base. For example, when looking at the salt NH4ClO4, you can see that it is composed of NH4+ and ClO4-. ClO4- is the conjugate base of a strong acid. NH4+ is the conjugate acid of a weak base (NH3). If the salt is composed of a strong acid and a weak base, then the salt is acidic.
Next, when looking at Na2S, we know see that it is composed of a weak acid (H2S) and a strong base (NaOH). This composition will create a basic salt.
A neutral salt is a salt consisting of an anion and cation that are not acidic or basic in character. For example NaCl is a salt, but the ions Na+ and Cl- do not change the pH of a solution.

[Jiane_Beach_1D]

Hey! I think it may just be the wording of the question that is confusing. In class we learned that if a salth has acidic ions then it is acidic and if a salt has basic ions then it is basic. Look at the ions that make up the salt and be careful because ions won't change the pH of a solution due to their properties.

[Nomi Heidari-Bateni 2K]

Here is a simple way to look at it:
If the salt has a cation from a weak base (for example NH4+), then it will make a solution more acidic.
If the salt has an anion from a weak acid (for example CN-), then it will make a solution more basic.
If the salt has a cation from a strong base and an anion from a strong acid, it will keep the solution neutral.

[Aanya Pramanik 1C]

Hi! I was pretty confused too and then I watched this video https://youtu.be/MXTsUBC0Nlk and it helped a lot!

[Sarah3C]

Does anyone know if we will have to determine if a salt is basic, acidic, or natural if both create weak acids or bases? We have not gone over this, but I wanted to know if there was rule for this possibility, too.

[Daniel N]

Does anyone know if we will have to determine if a salt is basic, acidic, or natural if both create weak acids or bases? We have not gone over this, but I wanted to know if there was rule for this possibility, too.

If the salt is created from both a weak acid and a weak base, then I would assume they would cancel out and end up neutral.