25B. Reactions of Ethanoic Acid

Pdst Chemistry

1 Mar 201705:52

Summary

TLDRThis experiment investigates the reactions of ethanoic acid with sodium carbonate, magnesium, and ethanol. Ethanoic acid, a weaker acid compared to common inorganic acids, exhibits typical acid properties. When ethanoic acid reacts with sodium carbonate, it produces carbon dioxide, which turns limewater milky. The reaction with magnesium forms magnesium ethanoate and releases hydrogen gas, causing a popping sound. Lastly, when mixed with ethanol and sulfuric acid as a catalyst, ethanoic acid forms an ester with a fruity smell. These reactions demonstrate the characteristic behavior of carboxylic acids.

Takeaways

🧪 The experiment studies the reactions of ethanoic acid with sodium carbonate, magnesium metal, and ethanol.
🥼 Ethanoic acid is weaker than common inorganic acids like sulfuric, hydrochloric, and nitric acid, but still shows typical acidic properties.
💨 Sodium carbonate reacts with ethanoic acid, producing carbon dioxide, which extinguishes a lighted taper.
🧊 The gas produced in the sodium carbonate-ethanoic acid reaction turns lime water milky, indicating the formation of calcium carbonate (chalk).
🔬 The reaction between ethanoic acid and sodium carbonate forms sodium ethanoate, water, and carbon dioxide.
⚡ Magnesium metal reacts with ethanoic acid, producing fizzing and releasing hydrogen gas, which causes a popping sound when ignited.
🔥 The reaction between magnesium and ethanoic acid forms magnesium ethanoate and hydrogen gas.
🍸 Ethanol reacts with glacial ethanoic acid in the presence of sulfuric acid (as a catalyst), producing a fruity smell.
🌸 The fruity smell results from the formation of ethyl ethanoate, an ester, from the reaction between ethanol and ethanoic acid.
🔑 These reactions demonstrate that ethanoic acid shows typical carboxylic acid properties when reacting with sodium carbonate, magnesium, and ethanol.

Q & A

What are the substances tested with ethanoic acid in this experiment?
-The substances tested with ethanoic acid are sodium carbonate, magnesium metal, and ethanol.
How does ethanoic acid compare to common inorganic acids like sulfuric, hydrochloric, and nitric acids?
-Ethanoic acid is a far weaker acid compared to common inorganic acids like sulfuric, hydrochloric, and nitric acids, but it is still strong enough to exhibit typical acid properties.
What is observed when ethanoic acid reacts with sodium carbonate?
-When ethanoic acid reacts with sodium carbonate, fizzing occurs, and carbon dioxide is released, which extinguishes a lighted taper brought near the mouth of the test tube.
What gas is produced during the reaction between ethanoic acid and sodium carbonate, and how is this gas confirmed?
-Carbon dioxide gas is produced during the reaction between ethanoic acid and sodium carbonate, and it is confirmed by passing the gas through lime water, which turns milky due to the formation of calcium carbonate.
What is the chemical equation for the reaction between ethanoic acid and sodium carbonate?
-The reaction between ethanoic acid and sodium carbonate produces sodium ethanoate, water, and carbon dioxide. The equation is: 2CH₃COOH + Na₂CO₃ → 2CH₃COONa + H₂O + CO₂.
What happens when magnesium metal reacts with ethanoic acid?
-When magnesium metal reacts with ethanoic acid, fizzing is observed, and a lighted taper produces a mild popping sound due to the release of hydrogen gas.
What causes the popping sound during the reaction between magnesium metal and ethanoic acid?
-The popping sound is caused by the explosive mixture of hydrogen gas and air, which is liberated during the reaction between magnesium metal and ethanoic acid.
What are the products of the reaction between ethanoic acid and magnesium metal?
-The reaction between ethanoic acid and magnesium metal produces magnesium ethanoate and hydrogen gas.
What occurs when ethanoic acid reacts with ethanol in the presence of concentrated sulfuric acid?
-When ethanoic acid reacts with ethanol in the presence of concentrated sulfuric acid, an ester (ethyl ethanoate) is formed, and the contents of the test tube acquire a fruity smell.
What role does sulfuric acid play in the reaction between ethanoic acid and ethanol?
-Sulfuric acid acts as a catalyst in the reaction between ethanoic acid and ethanol, speeding up the formation of the ester (ethyl ethanoate).

Outlines

00:00

🧪 Reaction of Ethanoic Acid with Sodium Carbonate

The paragraph explains the reaction between ethanoic acid and sodium carbonate. Ethanoic acid, while weaker than common inorganic acids, displays typical acidic properties. Sodium carbonate powder is added to ethanoic acid in a test tube, leading to fizzing and carbon dioxide release. The gas extinguishes a lighted taper and turns lime water milky due to the formation of calcium carbonate. The reaction equation shows the formation of sodium ethanoate, water, and carbon dioxide. This is similar to a previous experiment involving carbonate ions.

05:07

🔬 Reaction of Ethanoic Acid with Magnesium

This paragraph describes the reaction between ethanoic acid and magnesium metal. Magnesium ribbon is placed in a test tube containing dilute ethanoic acid, resulting in fizzing. A mild popping sound is heard when a lighted taper is brought near the tube. This is due to the formation of hydrogen gas, which creates an explosive mixture with air. The reaction forms magnesium ethanoate and hydrogen gas, with the popping sound explained by the presence of hydrogen.

🍎 Reaction of Ethanoic Acid with Ethanol

This section covers the reaction between ethanoic acid and ethanol, which leads to the formation of an ester. Ethanoic acid and ethanol are mixed, followed by the addition of concentrated sulfuric acid as a catalyst. After heating the mixture in hot water, the fruity smell of ethyl ethanoate (an ester) is detected. This reaction exemplifies the esterification process, showcasing ethanoic acid's typical behavior as a carboxylic acid.

Mindmap

Keywords

💡Ethanoic acid

Ethanoic acid, also known as acetic acid, is an organic compound with the formula CH3COOH. It is a weak acid, which means it does not dissociate completely in water. In the video, it is used to demonstrate typical acidic reactions, such as fizzing with sodium carbonate and reacting with magnesium to produce hydrogen gas. The script mentions that ethanoic acid is weaker than common inorganic acids like sulfuric acid but still exhibits acid properties.

💡Sodium carbonate

Sodium carbonate, commonly known as washing soda or soda ash, is a chemical compound with the formula Na2CO3. It is a base and is used in the script to demonstrate the reaction with ethanoic acid. When ethanoic acid is added to sodium carbonate, it produces carbon dioxide, which is observed as fizzing and can extinguish a lighted taper.

💡Magnesium

Magnesium is a chemical element with the symbol Mg and is an alkaline earth metal. In the script, magnesium metal reacts with ethanoic acid to produce magnesium ethanoate and hydrogen gas. The reaction is exothermic and can produce a mild popping sound due to the release of hydrogen gas, which is flammable and can react explosively with air.

💡Ethanol

Ethanol, with the chemical formula C2H5OH, is an organic compound and the alcohol found in alcoholic beverages. In the video, ethanol reacts with ethanoic acid in the presence of a catalyst, sulfuric acid, to form an ester with a fruity smell. This reaction is an esterification process, demonstrating the versatility of ethanoic acid in organic chemistry.

💡Carbon dioxide

Carbon dioxide is a chemical compound with the formula CO2. It is a gas at room temperature and is produced in the reaction between ethanoic acid and sodium carbonate. The script describes how carbon dioxide turns lime water milky due to the formation of calcium carbonate, a phenomenon used to test for the presence of carbonate ions.

💡Lime water

Lime water is a clear solution of calcium hydroxide in water. In the video, it is used to test for the presence of carbon dioxide, which reacts with calcium hydroxide to form calcium carbonate, causing the solution to turn milky. This is a classic test for carbonates and is demonstrated in the script.

💡Milkiness

Milkiness refers to the cloudy or opaque appearance of a liquid due to the presence of suspended particles. In the script, the milkiness of lime water is used as an indicator of the reaction between ethanoic acid and sodium carbonate, where the formation of calcium carbonate causes the solution to become cloudy.

💡Catalyst

A catalyst is a substance that increases the rate of a chemical reaction without being consumed in the process. In the script, concentrated sulfuric acid acts as a catalyst for the esterification reaction between ethanol and ethanoic acid, speeding up the formation of the ester without being used up.

💡Ester

An ester is a compound formed from an acid and an alcohol by the elimination of water. In the video, the ester ethyl ethanoate is formed when ethanol reacts with ethanoic acid in the presence of a catalyst. The fruity smell produced is characteristic of esters and is used to illustrate the esterification process.

💡Fizzy reaction

A fizzy reaction is a colloquial term for a chemical reaction that produces gas, often observable as bubbling or fizzing. In the video, the reaction between ethanoic acid and sodium carbonate is described as fizzy, indicating the release of carbon dioxide gas.

💡Metallic reaction

A metallic reaction typically involves a metal reacting with an acid to produce hydrogen gas and a metal salt. In the script, the reaction between ethanoic acid and magnesium metal is described, resulting in the formation of magnesium ethanoate and hydrogen gas, which is indicative of a typical metallic reaction.

Highlights

Investigation of ethanoic acid's reactions with sodium carbonate, magnesium, and ethanol.

Ethanoic acid is weaker than sulfuric, hydrochloric, and nitric acids but shows typical acid properties.

Reaction of ethanoic acid with sodium carbonate produces fizzing and carbon dioxide gas.

When a lighted taper is brought near the mouth of the test tube with sodium carbonate, the taper is extinguished.

Passing evolved gas through lime water turns it milky, indicating the presence of carbon dioxide.

Reaction between ethanoic acid and sodium carbonate forms sodium ethanoate and water.

Lime water turns milky due to calcium carbonate formation from carbon dioxide and lime water reaction.

The reaction of ethanoic acid with magnesium metal results in fizzing and the release of hydrogen gas.

The reaction of ethanoic acid with magnesium forms magnesium ethanoate and liberates hydrogen gas.

The popping sound when a lighted taper is near the test tube is due to hydrogen forming an explosive mixture with air.

Reaction of ethanoic acid with ethanol, using sulfuric acid as a catalyst, results in fruity-smelling ester formation.

Esterification between ethanoic acid and ethanol produces a fruity smell due to ethyl ethanoate.

The experiment demonstrates the typical properties of carboxylic acids reacting with sodium carbonate, magnesium, and ethanol.

The esterification reaction with ethanol is catalyzed by concentrated sulfuric acid and heated in water.

The formation of ethanoate ester is confirmed by the fruity odor of the reaction mixture after heating.