Ammonia And Acetic Acid Reaction

Simple Reactions of Carboxylic Acids as Acids

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This page looks at the simple reactions of carboxylic acids as acids, including their reactions with metals, metal hydroxides, carbonates and hydrogencarbonates, ammonia and amines.

The acidity of the carboxylic acids

Using the definition of an acid every bit a "substance which donates protons (hydrogen ions) to other things", the carboxylic acids are acidic because of the hydrogen in the -COOH group. In solution in h2o, a hydrogen ion is transferred from the -COOH group to a water molecule. For case, with ethanoic acrid, you lot get an ethanoate ion formed together with a hydroxonium ion, H_threeO⁺.

This reaction is reversible and, in the case of ethanoic acid, no more virtually 1% of the acid has reacted to class ions at any 1 time. (This is a rough-and-prepare effigy and varies with the concentration of the solution.)

These are therefore weak acids.

\[ CH_3COOH + H_2O \rightleftharpoons CH_3COO^- + H_3O^+\]

This equation is often simplified by removing the water to:

\[ CH_3COOH (aq) \rightleftharpoons CH_3COO^- (aq) + H^+\]

Even so, if you are going to use this second equation, you must include state symbols. They imply that the hydrogen ion is actually attached to a water molecule.

The pH of carboxylic acrid solutions

The pH depends on both the concentration of the acid and how hands information technology loses hydrogen ions from the -COOH group. Ethanoic acid is typical of the acids where the -COOH grouping is attached to a simple alkyl group. Typical lab solutions have pH'south in the 2 - 3 range, depending on their concentrations.

Methanoic acid is rather stronger than the other simple acids, and solutions have pH's well-nigh 0.5 pH units less than ethanoic acid of the same concentration.

Reactions of carboxylic acids with metals

Carboxylic acids react with the more than reactive metals to produce a salt and hydrogen. The reactions are just the same as with acids like hydrochloric acid, except they tend to be rather slower.

For example, dilute ethanoic acrid reacts with magnesium. The magnesium reacts to produce a colorless solution of magnesium ethanoate, and hydrogen is given off. If y'all use magnesium ribbon, the reaction is less vigorous than the same reaction with hydrochloric acrid, just with magnesium powder, both are so fast that you probably wouldn't notice much departure.

\[ 2CH_3COOH + Mg \rightarrow (CH_3COO)_2Mg + H_2\]

Reactions of carboxylic acids With metallic hydroxides

These are elementary neutralisation reactions and are just the same as any other reaction in which hydrogen ions from an acrid react with hydroxide ions. They are almost quickly and easily represented by the equation:

\[ H^+ (aq) + OH^- \rightarrow H_2O(50)\]

If yous mix dilute ethanoic acrid with sodium hydroxide solution, for case, y'all but get a colorless solution containing sodium ethanoate. The only sign that a change has happened is that the temperature of the mixture will have increased.

This change could well be represented by the ionic equation above, but if y'all want it, the total equation for this particular reaction is:

\[ CH_3COOH + NaOH \rightarrow CH_3COONa + H_2O\]

Reactions of carboxylic acids with carbonates and hydrogencarbonates

In both of these cases, a salt is formed together with carbon dioxide and h2o. Both are nigh easily represented by ionic equations.

For carbonates:

\[2H^+ (aq) + CO_3^{2-} \rightarrow H_2O (fifty) + CO_2 (g)\]

. . . and for hydrogencarbonates:

\[H^+ (aq) + HCO_3^{-} \rightarrow H_2O (l) + CO_2 (g)\]

If you pour some dilute ethanoic acid onto some white sodium carbonate or sodium hydrogencarbonate crystals, in that location is an firsthand fizzing as carbon dioxide is produced. Y'all end upwards with a colorless solution of sodium ethanoate.

With sodium carbonate, the full equation is:

\[ 2CH_3COOH + Na_2CO_3 \rightarrow 2CH_3COONa + H_2O + CO_2\]

. . . and for sodium hydrogencarbonate:

\[ CH_3COOH + NaHCO_3 \rightarrow CH_3COONa + H_2O + CO_2\]

There is very piddling obvious difference in the vigor of these reactions compared with the same reactions with dilute hydrochloric acrid. However, you lot would notice the difference if you used a slower reaction - for case with calcium carbonate in the form of a marble bit. With ethanoic acid, y'all would eventually produce a colorless solution of calcium ethanoate.

\[ 2CH_3COOH + CaCO_3 \rightarrow (CH_3COO)_2Ca + H_2O + CO_2\]

In this instance, the marble scrap would react noticeably more slowly with ethanoic acid than with hydrochloric acid.

Reactions of carboxylic acids with ammonia

Ethanoic acid reacts with ammonia in exactly the same fashion every bit any other acid does. It transfers a hydrogen ion to the lone pair on the nitrogen of the ammonia and forms an ammonium ion.

If y'all mix together a solution of ethanoic acid and a solution of ammonia, yous will go a colorless solution of ammonium ethanoate.

\[ CH_3COOH + NH_3 \rightarrow CH_3COONH_4\]

Reactions of carboxylic acids with amines

Amines are compounds in which one or more of the hydrogen atoms in an ammonia molecule have been replaced by a hydrocarbon grouping such equally an alkyl grouping. For simplicity, we'll just await at compounds where only one of the hydrogen atoms has been replaced. These are called primary amines.

Simple primary amines include:

The small amines are very like indeed to ammonia in many ways. For example, they odor very much similar ammonia and are merely equally soluble in water. Because all you have done to an ammonia molecule is swap a hydrogen for an alkyl group, the lone pair is still there on the nitrogen atom.

That means that they volition react with acids (including carboxylic acids) in just the same way as ammonia does. For example, ethanoic acid reacts with methylamine to produce a colorless solution of the table salt methylammonium ethanoate.

However complicated the amine, because all of them take got a lonely pair on the nitrogen cantlet, you would get the same sort of reaction.

Ammonia And Acetic Acid Reaction,

Source: https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Supplemental_Modules_%28Organic_Chemistry%29/Carboxylic_Acids/Reactivity_of_Carboxylic_Acids/Simple_Reactions_of_Carboxylic_Acids_as_Acids

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