Does anybody know an easy way to remember which cations/anions relate to acidic/basic salts?
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Does anybody know an easy way to remember which cations/anions relate to acidic/basic salts?
I remember learning this in 14A, but does anyone have an easy method they use?
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Re: Does anybody know an easy way to remember which cations/anions relate to acidic/basic salts?
I think the only "easy" way to know them is to memorize the different strong and weak acids.To determine if a salt is acidic or basic you compare the Ka to the Kb. If Ka > Kb, the ion is acidic; if Kb > Ka, the ion is basic.
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Re: Does anybody know an easy way to remember which cations/anions relate to acidic/basic salts?
I've found that the easiest method for me is to remember which acids and bases are strong.
Strong Acids: SO I BRought NO CLean CLOthes (H2SO4, HI, HBr, HNO3, HCl, HClO4, HClO3)
Strong Bases: Group 1A metal hydroxides (LiOH, NaOH, KOH, RbOH, CsOH), heavy Group 2A metal hydroxides (Ca(OH)2, Sr(OH)2, Ba(OH)2)
Then, when given a salt, you can determine whether it's an acidic or basic salt by looking at its individual cation and anion.
If the cation comes from a strong base and the anion comes from a strong acid, the salt will be neutral.
If the cation comes from a strong base and the anion comes from a weak acid, the salt will be basic.
If the cation comes from a weak base and the anion comes from a strong acid, the salt will be acidic.
I hope this was helpful!
Strong Acids: SO I BRought NO CLean CLOthes (H2SO4, HI, HBr, HNO3, HCl, HClO4, HClO3)
Strong Bases: Group 1A metal hydroxides (LiOH, NaOH, KOH, RbOH, CsOH), heavy Group 2A metal hydroxides (Ca(OH)2, Sr(OH)2, Ba(OH)2)
Then, when given a salt, you can determine whether it's an acidic or basic salt by looking at its individual cation and anion.
If the cation comes from a strong base and the anion comes from a strong acid, the salt will be neutral.
If the cation comes from a strong base and the anion comes from a weak acid, the salt will be basic.
If the cation comes from a weak base and the anion comes from a strong acid, the salt will be acidic.
I hope this was helpful!
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Re: Does anybody know an easy way to remember which cations/anions relate to acidic/basic salts?
Hi,
I always follow this chart to determine whether a given salt is acidic, basic, or neutral:
Note: You must first derive the parent acid and parent base of the salt in order to use this chart. (A salt is always the product of an acid-base neutralization reaction.) The cation of the salt is always from the base of the neutralization reaction, and the anion of the salt is always from the acid of the neutralization reaction. Then, determine whether the parent acid and parent base are strong or weak.
Example: NH4Cl (the salt discussed in Dr. Lavelle's 01/14 lecture)
In an aqueous solution, NH4Cl dissociates/ionizes to form NH4+ and Cl-. These ions are derived from the parent weak base (NH3) and parent strong acid (HCl), respectively. Based on the above chart, the neutralization reaction between a weak base and strong acid yields an acidic salt.
Hope this helps!
I always follow this chart to determine whether a given salt is acidic, basic, or neutral:
Note: You must first derive the parent acid and parent base of the salt in order to use this chart. (A salt is always the product of an acid-base neutralization reaction.) The cation of the salt is always from the base of the neutralization reaction, and the anion of the salt is always from the acid of the neutralization reaction. Then, determine whether the parent acid and parent base are strong or weak.
Example: NH4Cl (the salt discussed in Dr. Lavelle's 01/14 lecture)
In an aqueous solution, NH4Cl dissociates/ionizes to form NH4+ and Cl-. These ions are derived from the parent weak base (NH3) and parent strong acid (HCl), respectively. Based on the above chart, the neutralization reaction between a weak base and strong acid yields an acidic salt.
Hope this helps!
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Re: Does anybody know an easy way to remember which cations/anions relate to acidic/basic salts?
N Kanuri 2E wrote:I've found that the easiest method for me is to remember which acids and bases are strong.
Strong Acids: SO I BRought NO CLean CLOthes (H2SO4, HI, HBr, HNO3, HCl, HClO4, HClO3)
Strong Bases: Group 1A metal hydroxides (LiOH, NaOH, KOH, RbOH, CsOH), heavy Group 2A metal hydroxides (Ca(OH)2, Sr(OH)2, Ba(OH)2)
Then, when given a salt, you can determine whether it's an acidic or basic salt by looking at its individual cation and anion.
If the cation comes from a strong base and the anion comes from a strong acid, the salt will be neutral.
If the cation comes from a strong base and the anion comes from a weak acid, the salt will be basic.
If the cation comes from a weak base and the anion comes from a strong acid, the salt will be acidic.
I hope this was helpful!
Thank you this was very helpful! I can also add that usually if the acid starts with an H it is strong, if it starts with an N it is probably a base. This is not helpful if you are only given the cation though.
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