Now, ionic salts represent ionic compounds that are formed when an acid or base undergo a neutralization reaction. Here. For example, we have hydrochloric acid reacting with sodium hydroxide. When they react, we're gonna create our ionic salt which is basically sodium chloride aqueous and then we'll have water being formed as well. Now, this ionic salt of sodium chloride, we're gonna say based on its identity, the salt can either be acidic, basic or neutral. So in these series of videos, we're gonna take a look at the steps necessary to determine if our ionic salt overall is acidic, basic or neutral.
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concept
Ionic Salts - Cations
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So remember that ionic salts are ionic compounds. An ionic compounds are composed of a positive ion called a cion and a negative ion called an anion. Here, let's first take a look at the cion rules. Here, we're gonna say C ions can be either acidic or neutral based on the magnitude of their charges or their identity. So here we're gonna break up cation ions into three groups. We have our main group metals, our transition metals and are positively charged a means for main group metals, they have to have a charge of plus three or higher to be a sick. Here, we have T four bromide 10, 4 bromide when it breaks up into ions produces T four ion plus a bromide ion. Here, we're not worrying about that. It releases four bromide ions. We're just focused on the fact that a bromide ion appears because we've created a main group metal, a cion that has a charge of plus three or higher, then it will be ac. So this tin four ion is acidic for transition metals, they only need to be plus two or higher in order to be acidic. Here, we have zinc chloride, which breaks up into zinc, two plus ion. And the chloride ion, zinc has met the minimum requirement of having at least a charge of plus two zinc would be an acidic cat island. And then finally, we're gonna say that positive A means which we've talked about before in other sections, positive A means are weak acids. So here a positive mean would be acidic. Here we have ammonium nitrate. It will break up into the ammonium ion plus the nitrate ion. Ammonium is our positively charged dome. And because it's a positively charged dome, it's automatically going to be acidic. So remember in this section, we're only looking at the positive ion, the cion, the negative ions, we worry about them later on. But right now, remember cion, we look at the main group metals, the transition metals or if a positive amine is present, knowing these rules will allow you to determine if that positive ion is acidic or neutral.
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example
Ionic Salts Example
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Which of the following reactions will create an acidic solution when dissolved in an aqueous solvent. So here we have these five choices. We're looking for an acidic solution. So we have to look and see what kind of cat ion we form. In the first one, we have sodium fluoride, we produce N A plus. Here we have lithium acetate. So we're gonna produce lithium plus here, this is manganese five chloride. So we've created manganese five ion strontium su sulfide breeds strontium ion and then calcium cyanide creates the calcium ion. Now we're going to say that sodium lithium strontium and calcium, they're all main group metals. Remember for the main group metal to be acidic, it has to have a charge of plus three or higher. None of these ions meet that minimum requirement of plus three charge. So none of them would create an acidic solution. They all would be neutral. Here, if we look at manganese, five manganese is a transition metal transition metals only need to have a charge of plus two or higher to be considered acidic. Manganese is five plus, it's definitely met that requirement. So here this could create an acidic solution when dissolved in an aqueous solvent. Remember, we're looking to what creates an acidic solution. So we're looking at the C ions that are formed in each of these compounds. So we find the C ion, the positively charged ion and look at the magnitude of its charge to see if it can be acidic or neutral.
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Problem
Problem
Which of the following compounds would decrease the pH of solution?
a) SrBr2 b) KSH c) NaN3 d) NiP e) Hg2Cl2
A
SrBr2
B
KSH
C
NaN3
D
NiP
E
Hg2Cl2
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concept
Cation Solubility
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Now recall that solubility is a chemical property that deals with the ability of a solute to become dissolved in a solvent. Here, we're going to say for an acidic ion, the solubility increases when placed in a basic solution. So now we're gonna have to identify if a cation is acidic or neutral, the acidic ones will become more soluble within a basic solution. Nothing will happen to the neutral ones. So, keep this in mind when we take a look at cion solubility.
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example
Ionic Salts Example
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Which of the following compounds will be the most soluble in a basic solution. So here we're wanting to take a look at the C ions when they dissolve, we're gonna create this positive amine. Remember, positive amines are acidic. Since it's an acidic ion, its solubility will increase within a basic solution. So this would be an answer. Next, we have Cobalt one. Remember transition metals need to be plus two or higher in order to be acidic. This one does not meet that minimum requirement. So it is neutral. Next, we have Barry Mayan barium is a group on main group metal. They have to be plus three or higher in order to be acidic. Here doesn't meet that minimum requirement. So it's neutral. Next, we have lead two ion. Same thing, lead two is a main group metal. It has to be at least plus three or higher to be acidic. And then finally, here we have potassium which only plus one as a main group metal. So here, the only cion that is acidic in nature would be the first one we produced a positively charged amine. Since it is an acidic ion, its sole would increase within a basic solution. So here our answer is option A.
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concept
Ionic Salts - Anions
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Now, in our exploration to understand ionic salts, we've now come to anions. Anions represent negatively charged ions. Anions can either be basic or neutral based on their acceptance of a proton. Now remember a proton is just represented by an H plus ion. If we take a look here, we're gonna say add an H plus to the an, if a weak acid is created, then your anion is basic. So if we take a look here, we have potassium fluoride. So it breaks up into K positive and F minus F minus is our anion. We're gonna add an H plus to it. When we do that, we create HF which is Hydrofluoric acid, which is a weak acid. That means that the fluoride ion is basic. That's because here we have a weak acid. If you're a weak acid, you're gonna create a stronger conjugate base, just strong enough that it's classified as being basic over here on this side. When we add an H plus to an anion, if a strong acid is created, then the anion is neutral. Here we have sodium chloride which breaks up into sodium ion plus the chloride ion. Here, we're gonna add an H plus to the chloride ion to give us hcl hydrochloric acid, which is a strong acid because we created a strong acid. That means its conjugate base is gonna be extremely weak, so weak that we see it as being neutral. So this chloride ion here would be neutral. So just remember when we have a negatively charged ion, add an H plus to it. If you create a weak acid, then the negative ion is basic. If you create a strong acid, then the negative ion will be neutral.
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example
Ionic Salts Example
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Which of the following compounds will create a basic solution when dissolved in water. Here, we're looking to create a basic solution, which means we need to look at the anion, the negative ion involved. Here, we're going to see that this breaks up into chloride ion, nitrate ion, her chloride ion bromide ion and iodide ion to each of these, we add an H plus to them creating an acid. So here we're creating perchloric acid, hydro Bromma acid and hydro ionic acid. We're gonna say here that hydrochloric acid, hydro um per perchloric acid, hydro brom acid and hydrotic acid all represent strong acids. That means since they're strong acids, that means the negative ions um that they came from would be neutral. So all of these are neutral. Here, we have nitrous acid, which is a weak acid. Since it's a weak acid, that means its negative ion is basic. So this is the only basic anion that we have present and it will create a basic solution when dissolved in water. That means option B is our correct answer.
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Problem
Problem
Which of the following compounds would increase the pH of solution?
a) SrBr2 b) K c) NaN3 d) NiBr2 e) Hg2Cl2
A
SrBr2
B
K
C
NaN3
D
NiBr2
E
Hg2Cl2
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example
Ionic Salts Example
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Here, when it comes to the anion solubility, we're going to say that for the basic ion, the solubility increases when placed in an acidic solution. So here we're gonna say what will happen to the solubility of the following ionic compound when it is placed in a solution with a ph of 4.0. Well, here the solution has a ph that is less than seven. So this represents an acidic solution. Here we break this up. We're looking to see if it's a basic ion. So we're looking at the anion portion. So C three H 503 minus for the anion, we add an H plus to it. When I add an H plus to it, I create a weak oxy aid since I created a weak acid, that means that my negative ion will be basic. So this means that if I take this basic ion and I place it within the solution, it's gonna cause the ph to increase to become more basic. So here um what will happen to the soil of this compound? It is a basic anion. So its liability increases within the acidic solution. So here the answer would be option B.
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Problem
Problem
Which of the following compounds would have an increase in solubility when placed into an acidic solution?