Define alcohol as a family of organic compounds.

An alcohol is an organic compound containing the hydroxyl functional group (-OH) attached to a carbon chain.

True or False? Alcohols are classified as hydrocarbons.

False. Alcohols are not hydrocarbons because they contain oxygen as well as carbon and hydrogen. Hydrocarbons contain only carbon and hydrogen.

What is the general formula of the alcohol homologous series?

The general formula is C n H 2n+1 OH.

Alcohols are excellent .......... because they can dissolve many substances that .......... cannot.

Alcohols are excellent solvents because they can dissolve many substances that water cannot.

Give two uses of alcohols as fuels.

Alcohols are used as: Fuels in spirit burners and camping stoves Biofuels for cars

What does the -ol ending in an alcohol name indicate?

The -ol ending indicates that the molecule contains a hydroxyl group (-OH) and belongs to the alcohol homologous series.

How is the carbon chain numbered when naming an alcohol?

Carbon atoms are numbered from the end closest to the -OH group , so that the hydroxyl group receives the lowest possible number.

True or False? The molecular formula of propan-1-ol is C 3 H 7 OH.

True. Using the general formula C n H 2n+1 OH with n = 3 gives C 3 H 7 OH.

Give the molecular formula of heptan-2-ol.

The molecular formula of heptan-2-ol is C 7 H 15 OH, using the general formula C n H 2n+1 OH with n = 7.

Miscibility describes how well two liquids mix or dissolve together. If two liquids are miscible they form a single solution; if immiscible they do not mix.

Which small alcohols are miscible with water?

Methanol, ethanol and propanol are miscible with water. Their small size and -OH group allow them to mix completely.

True or False? The solubility of straight-chain alcohols in water increases as the length of the carbon chain increases.

False. Solubility decreases as the carbon chain gets longer. From butanol onwards, the long hydrocarbon part of the molecule does not mix well with water, and this effect grows with chain length.

From .......... onwards, the solubility of straight-chain alcohols in water decreases significantly as the .......... gets longer.

From butanol onwards, the solubility of straight-chain alcohols in water decreases significantly as the carbon chain gets longer.

How does the boiling point change as straight-chain alcohols increase in size?

The boiling point increases as the molecule gets bigger because larger molecules have stronger intermolecular forces, which require more energy to overcome.

What are intermolecular forces in the context of alcohols?

Intermolecular forces are the weak attractions between alcohol molecules. As molecules get larger, these forces become stronger, raising the energy needed to melt or boil the substance.

True or False? The boiling point trend in straight-chain alcohols is more regular than the melting point trend.

True. Boiling points increase steadily with chain length, whereas melting points show a less regular trend across the series.

Why do the melting and boiling points of alcohols generally increase as molecules get larger?

Larger alcohol molecules have stronger intermolecular forces between them. More energy is needed to overcome these forces, so the melting and boiling points are higher.

Larger alcohol molecules have stronger .......... forces, so .......... energy is required to overcome them and allow the substance to boil.

Larger alcohol molecules have stronger intermolecular forces, so more energy is required to overcome them and allow the substance to boil.

What are carboxylic acids ?

Carboxylic acids are a homologous series of organic compounds that contain the -COOH (carboxyl) functional group.

What is the general formula for the carboxylic acid homologous series?

The general formula is C n H 2n+1 COOH, where n is the number of carbon atoms before the -COOH group.

True or False? Carboxylic acids are hydrocarbons.

False. Carboxylic acids are not hydrocarbons because they contain oxygen (in the -COOH group), whereas hydrocarbons contain only carbon and hydrogen.

Ethanoic acid (CH 3 COOH) is the carboxylic acid found in .......... . It is non-toxic, which is why it is used safely in .......... and household cleaning products.

Ethanoic acid (CH 3 COOH) is the carboxylic acid found in vinegar . It is non-toxic, which is why it is used safely in food and household cleaning products.

What is the carboxyl group ?

The carboxyl group is the -COOH functional group found in carboxylic acids, consisting of a carbon atom double-bonded to one oxygen and single-bonded to an -OH group.

State three uses of carboxylic acids in manufacturing.

Carboxylic acids are used as building blocks for: Preservatives (to prevent food spoiling) Soaps Medicines

State the molecular formula of propanoic acid using the general formula C n H 2n+1 COOH.

The molecular formula of propanoic acid is C 2 H 5 COOH. Propanoic acid has 3 carbons in total, but one carbon is in the -COOH group, so n = 2. Applying the formula: C 2 H (2×2)+1 COOH = C 2 H 5 COOH.

True or False? When naming a carboxylic acid, the carbon of the -COOH group is included in the carbon chain count.

True. The -COOH carbon must always be counted as part of the longest chain, so a 6-carbon carboxylic acid is named hexanoic acid (not pentanoic acid + COOH).

The name of a straight-chain carboxylic acid is formed from a .......... indicating the number of carbon atoms and the ending ".........." to show it is a carboxylic acid.

The name of a straight-chain carboxylic acid is formed from a prefix indicating the number of carbon atoms and the ending "-oic acid" to show it is a carboxylic acid.

State the molecular formula of octanoic acid.

The molecular formula of octanoic acid is C 7 H 15 COOH. Octanoic acid has 8 carbons in total; one is in -COOH, so n = 7. Applying C n H 2n+1 COOH: C 7 H (2×7)+1 COOH = C 7 H 15 COOH.

What does miscible mean?

A miscible liquid is one that mixes completely with another liquid (usually water) in all proportions, forming a single uniform solution.

Name the four shortest carboxylic acids that are miscible with water.

The four shortest carboxylic acids that are miscible with water are: Methanoic acid Ethanoic acid Propanoic acid Butanoic acid

True or False? Pentanoic acid is miscible with water.

False. From pentanoic acid onwards, solubility in water decreases significantly. Pentanoic acid has a solubility of only 3.7 g per 100 g of water — it is not miscible.

How does the solubility of carboxylic acids in water change as the carbon chain length increases, and why?

Solubility decreases as chain length increases because the long hydrocarbon part of the molecule does not mix well with water. This effect becomes more significant as the chain grows longer.

From .......... acid onwards, the solubility of carboxylic acids in water .......... significantly as the carbon chain gets longer.

From pentanoic acid onwards, the solubility of carboxylic acids in water decreases significantly as the carbon chain gets longer.

How do the boiling points of carboxylic acids change as the molecules get bigger?

The boiling points of carboxylic acids increase as the molecules get bigger, showing a clear and predictable trend.

True or False? The trend in melting points of carboxylic acids is as regular and predictable as the trend in alkane boiling points.

False. The trend in boiling points is clear and predictable, but the trend in melting points is less regular, though both generally increase with chain length.

Why do the melting and boiling points of carboxylic acids increase as chain length increases?

As carboxylic acid molecules get larger, the strength of the intermolecular forces increases. More energy is needed to overcome these stronger forces, so the melting and boiling points generally increase.

As carboxylic acid molecules get larger, the strength of the .......... increases, so .......... energy is needed to overcome these forces during melting and boiling.

As carboxylic acid molecules get larger, the strength of the intermolecular forces increases, so more energy is needed to overcome these forces during melting and boiling.

Name the four types of substance that carboxylic acids can react with to form salts.

Carboxylic acids can react with: Metals Metal oxides Metal hydroxides Metal carbonates

What is a metal alkanoate ?

A metal alkanoate is the salt formed when a carboxylic acid reacts with a metal, metal oxide, metal hydroxide or metal carbonate. The name ends in "-anoate" (e.g. ethanoate from ethanoic acid).

When a carboxylic acid reacts with a metal, the products are a .......... and .......... gas.

When a carboxylic acid reacts with a metal, the products are a salt (metal alkanoate) and hydrogen gas.

True or False? Copper reacts with ethanoic acid to produce copper ethanoate and hydrogen.

False. Copper is below hydrogen in the electrochemical series, so it does not react with carboxylic acids. Only metals above hydrogen in the electrochemical series will react.

State the word equation for the reaction between a metal carbonate and a carboxylic acid, and name the three products.

The word equation is: metal carbonate + carboxylic acid → metal alkanoate + water + carbon dioxide. The three products are a salt (metal alkanoate), water and carbon dioxide gas.

How is the salt name derived from the carboxylic acid name?

The salt name is derived by replacing the "-oic acid" ending of the carboxylic acid name with "-anoate". For example, ethanoic acid forms ethanoate salts and propanoic acid forms propanoate salts.

Sodium hydroxide reacts with butanoic acid in a .......... reaction to form .......... and water.

Sodium hydroxide reacts with butanoic acid in a neutralisation reaction to form sodium butanoate and water.

True or False? When a carboxylic acid reacts with a metal oxide, fizzing is observed and a salt and water are produced.

False. The reaction of a carboxylic acid with a metal oxide produces a salt and water only — no gas is produced. Fizzing (effervescence) occurs in reactions with metals (hydrogen) or metal carbonates (carbon dioxide).

Write the word equation for the reaction between magnesium and ethanoic acid.

The word equation is: magnesium + ethanoic acid → magnesium ethanoate + hydrogen.

Write the word equation for the reaction between calcium carbonate and pentanoic acid.

The word equation is: calcium carbonate + pentanoic acid → calcium pentanoate + water + carbon dioxide.

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Everyday Consumer Products (SQA National 5 Chemistry): Flashcards

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Define alcohol as a family of organic compounds.

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Cards in this collection (47)

Define alcohol as a family of organic compounds.
An alcohol is an organic compound containing the hydroxyl functional group (-OH) attached to a carbon chain.
True or False?
Alcohols are classified as hydrocarbons.
False.
Alcohols are not hydrocarbons because they contain oxygen as well as carbon and hydrogen. Hydrocarbons contain only carbon and hydrogen.
What is the general formula of the alcohol homologous series?
The general formula is C_nH_2n+1OH.
Alcohols are excellent .......... because they can dissolve many substances that .......... cannot.
Alcohols are excellent solvents because they can dissolve many substances that water cannot.
Give two uses of alcohols as fuels.
Alcohols are used as:
1. Fuels in spirit burners and camping stoves
2. Biofuels for cars
What does the -ol ending in an alcohol name indicate?
The -ol ending indicates that the molecule contains a hydroxyl group (-OH) and belongs to the alcohol homologous series.
How is the carbon chain numbered when naming an alcohol?
Carbon atoms are numbered from the end closest to the -OH group, so that the hydroxyl group receives the lowest possible number.
True or False?
The molecular formula of propan-1-ol is C₃H₇OH.
True.
Using the general formula C_nH_2n+1OH with n = 3 gives C₃H₇OH.
Give the molecular formula of heptan-2-ol.
The molecular formula of heptan-2-ol is C₇H₁₅OH, using the general formula C_nH_2n+1OH with n = 7.
Define miscibility.
Miscibility describes how well two liquids mix or dissolve together. If two liquids are miscible they form a single solution; if immiscible they do not mix.
Which small alcohols are miscible with water?
Methanol, ethanol and propanol are miscible with water. Their small size and -OH group allow them to mix completely.
True or False?
The solubility of straight-chain alcohols in water increases as the length of the carbon chain increases.
False.
Solubility decreases as the carbon chain gets longer. From butanol onwards, the long hydrocarbon part of the molecule does not mix well with water, and this effect grows with chain length.
From .......... onwards, the solubility of straight-chain alcohols in water decreases significantly as the .......... gets longer.
From butanol onwards, the solubility of straight-chain alcohols in water decreases significantly as the carbon chain gets longer.
How does the boiling point change as straight-chain alcohols increase in size?
The boiling point increases as the molecule gets bigger because larger molecules have stronger intermolecular forces, which require more energy to overcome.
What are intermolecular forces in the context of alcohols?
Intermolecular forces are the weak attractions between alcohol molecules. As molecules get larger, these forces become stronger, raising the energy needed to melt or boil the substance.
True or False?
The boiling point trend in straight-chain alcohols is more regular than the melting point trend.
True.
Boiling points increase steadily with chain length, whereas melting points show a less regular trend across the series.
Why do the melting and boiling points of alcohols generally increase as molecules get larger?
Larger alcohol molecules have stronger intermolecular forces between them. More energy is needed to overcome these forces, so the melting and boiling points are higher.
Larger alcohol molecules have stronger .......... forces, so .......... energy is required to overcome them and allow the substance to boil.
Larger alcohol molecules have stronger intermolecular forces, so more energy is required to overcome them and allow the substance to boil.
What are carboxylic acids?
Carboxylic acids are a homologous series of organic compounds that contain the -COOH (carboxyl) functional group.
What is the general formula for the carboxylic acid homologous series?
The general formula is C_nH_2n+1COOH, where n is the number of carbon atoms before the -COOH group.
True or False?
Carboxylic acids are hydrocarbons.
False.
Carboxylic acids are not hydrocarbons because they contain oxygen (in the -COOH group), whereas hydrocarbons contain only carbon and hydrogen.
Ethanoic acid (CH₃COOH) is the carboxylic acid found in ........... It is non-toxic, which is why it is used safely in .......... and household cleaning products.
Ethanoic acid (CH₃COOH) is the carboxylic acid found in vinegar. It is non-toxic, which is why it is used safely in food and household cleaning products.
What is the carboxyl group?
The carboxyl group is the -COOH functional group found in carboxylic acids, consisting of a carbon atom double-bonded to one oxygen and single-bonded to an -OH group.
State three uses of carboxylic acids in manufacturing.
Carboxylic acids are used as building blocks for:
1. Preservatives (to prevent food spoiling)
2. Soaps
3. Medicines
State the molecular formula of propanoic acid using the general formula C_nH_2n+1COOH.
The molecular formula of propanoic acid is C₂H₅COOH.
Propanoic acid has 3 carbons in total, but one carbon is in the -COOH group, so n = 2. Applying the formula: C₂H_(2×2)+1COOH = C₂H₅COOH.
True or False?
When naming a carboxylic acid, the carbon of the -COOH group is included in the carbon chain count.
True.
The -COOH carbon must always be counted as part of the longest chain, so a 6-carbon carboxylic acid is named hexanoic acid (not pentanoic acid + COOH).
The name of a straight-chain carboxylic acid is formed from a .......... indicating the number of carbon atoms and the ending ".........." to show it is a carboxylic acid.
The name of a straight-chain carboxylic acid is formed from a prefix indicating the number of carbon atoms and the ending "-oic acid" to show it is a carboxylic acid.
State the molecular formula of octanoic acid.
The molecular formula of octanoic acid is C₇H₁₅COOH.
Octanoic acid has 8 carbons in total; one is in -COOH, so n = 7. Applying C_nH_2n+1COOH: C₇H_(2×7)+1COOH = C₇H₁₅COOH.
What does miscible mean?
A miscible liquid is one that mixes completely with another liquid (usually water) in all proportions, forming a single uniform solution.
Name the four shortest carboxylic acids that are miscible with water.
The four shortest carboxylic acids that are miscible with water are:
1. Methanoic acid
2. Ethanoic acid
3. Propanoic acid
4. Butanoic acid
True or False?
Pentanoic acid is miscible with water.
False.
From pentanoic acid onwards, solubility in water decreases significantly. Pentanoic acid has a solubility of only 3.7 g per 100 g of water — it is not miscible.
How does the solubility of carboxylic acids in water change as the carbon chain length increases, and why?
Solubility decreases as chain length increases because the long hydrocarbon part of the molecule does not mix well with water. This effect becomes more significant as the chain grows longer.
From .......... acid onwards, the solubility of carboxylic acids in water .......... significantly as the carbon chain gets longer.
From pentanoic acid onwards, the solubility of carboxylic acids in water decreases significantly as the carbon chain gets longer.
How do the boiling points of carboxylic acids change as the molecules get bigger?
The boiling points of carboxylic acids increase as the molecules get bigger, showing a clear and predictable trend.
True or False?
The trend in melting points of carboxylic acids is as regular and predictable as the trend in alkane boiling points.
False.
The trend in boiling points is clear and predictable, but the trend in melting points is less regular, though both generally increase with chain length.
Why do the melting and boiling points of carboxylic acids increase as chain length increases?
As carboxylic acid molecules get larger, the strength of the intermolecular forces increases. More energy is needed to overcome these stronger forces, so the melting and boiling points generally increase.
As carboxylic acid molecules get larger, the strength of the .......... increases, so .......... energy is needed to overcome these forces during melting and boiling.
As carboxylic acid molecules get larger, the strength of the intermolecular forces increases, so more energy is needed to overcome these forces during melting and boiling.
Name the four types of substance that carboxylic acids can react with to form salts.
Carboxylic acids can react with:
1. Metals
2. Metal oxides
3. Metal hydroxides
4. Metal carbonates
What is a metal alkanoate?
A metal alkanoate is the salt formed when a carboxylic acid reacts with a metal, metal oxide, metal hydroxide or metal carbonate. The name ends in "-anoate" (e.g. ethanoate from ethanoic acid).
When a carboxylic acid reacts with a metal, the products are a .......... and .......... gas.
When a carboxylic acid reacts with a metal, the products are a salt (metal alkanoate) and hydrogen gas.
True or False?
Copper reacts with ethanoic acid to produce copper ethanoate and hydrogen.
False.
Copper is below hydrogen in the electrochemical series, so it does not react with carboxylic acids. Only metals above hydrogen in the electrochemical series will react.
State the word equation for the reaction between a metal carbonate and a carboxylic acid, and name the three products.
The word equation is: metal carbonate + carboxylic acid → metal alkanoate + water + carbon dioxide.
The three products are a salt (metal alkanoate), water and carbon dioxide gas.
How is the salt name derived from the carboxylic acid name?
The salt name is derived by replacing the "-oic acid" ending of the carboxylic acid name with "-anoate". For example, ethanoic acid forms ethanoate salts and propanoic acid forms propanoate salts.
Sodium hydroxide reacts with butanoic acid in a .......... reaction to form .......... and water.
Sodium hydroxide reacts with butanoic acid in a neutralisation reaction to form sodium butanoate and water.
True or False?
When a carboxylic acid reacts with a metal oxide, fizzing is observed and a salt and water are produced.
False.
The reaction of a carboxylic acid with a metal oxide produces a salt and water only — no gas is produced. Fizzing (effervescence) occurs in reactions with metals (hydrogen) or metal carbonates (carbon dioxide).
Write the word equation for the reaction between magnesium and ethanoic acid.
The word equation is: magnesium + ethanoic acid → magnesium ethanoate + hydrogen.
Write the word equation for the reaction between calcium carbonate and pentanoic acid.
The word equation is: calcium carbonate + pentanoic acid → calcium pentanoate + water + carbon dioxide.

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