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24 Dec 2025
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Understanding Carboxylic Acids in GCSE Chemistry
Zainab
@zainab_02839
1 / 6
Carboxylic Acids
You'll recognise carboxylic acids by their distinctive -COOH functional group - it's like their chemical fingerprint. This group contains both a carbon double-bonded to oxygen and a hydroxyl group attached to the same carbon.
The simplest example is methanoic acid (HCOOH), which you might know as formic acid. It's the same stuff that makes ant bites sting!
Quick Tip: Remember that all carboxylic acids end in "-oic acid" when you're naming them.
Reacting Carboxylic Acids
Carboxylic acids behave just like other acids you've studied, but they react more slowly because they're weaker. Think of them as the "gentle" acids of the chemistry world.
They follow the same three classic acid reactions you need to remember: with metals , with carbonates , and with alkalis .
These reactions are slower than with strong acids like hydrochloric acid, but they still fizz with carbonates and produce hydrogen gas with metals.
Exam Tip: You'll often get asked to write word equations for these three reactions - practice them!
Weak Acids
Here's why carboxylic acids react slowly: they're weak acids. This doesn't mean they're rubbish at being acids - it's a specific scientific term!
Strong acids completely split apart (ionise) in water, whilst weak acids only partially ionise. Picture it like this: in a room full of strong acid molecules, they all break apart, but in a room of weak acid molecules, only some of them split up.
The equation shows methanoic acid reversibly forming oxonium ions and methanoate ions. That double arrow (⇌) tells you it's reversible - some molecules break apart whilst others join back together.
Key Point: Equal volumes of strong and weak acids have different H⁺ concentrations - this affects their reaction rates.
Making Esters
Now for something that smells amazing! When carboxylic acids react with alcohols, they create esters - the compounds responsible for most fruity smells.
This reaction needs sulphuric acid as a catalyst to speed things up. The general equation is simple: carboxylic acid + alcohol ⇌ ester + water.
A classic example is ethanoic acid (vinegar) reacting with methanol to make methyl ethanoate. Notice the reversible arrow again - this reaction can go both ways.
Remember: Water is always formed when making esters - it's a condensation reaction!
Naming Esters
Naming esters follows a simple two-part rule that'll save you marks in exams. The first part comes from the alcohol, and the second part comes from the acid.
Take propyl ethanoate: "propyl" comes from propanol (the alcohol), and "ethanoate" comes from ethanoic acid. Just swap the "-oic acid" ending for "-oate" when naming the acid part.
Think of it like a surname system - the alcohol gives the first name, the acid gives the family name!
Memory Trick: Alcohol first, acid second - just like "ladies first" but for molecules!
Properties of Esters
Esters are the superstars of the smell world! They're volatile (evaporate easily at room temperature) and have lovely sweet or fruity smells.
This makes them perfect for perfumes and food flavourings. That artificial banana smell in sweets? That's an ester! Same with many perfumes and fruit-flavoured drinks.
Their volatility means they escape into the air easily, which is exactly what you want for something that needs to reach your nose.
Real-World Connection: Next time you smell artificial fruit flavouring, you're detecting ester molecules!
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THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
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This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
Understanding Carboxylic Acids in GCSE Chemistry
Zainab
@zainab_02839
Carboxylic acids are everywhere around you - from the vinegar in your kitchen to the fruity smells in your favourite sweets. These compounds contain a special -COOH functional groupthat gives them unique properties and makes them incredibly useful in... Show more
Carboxylic Acids
You'll recognise carboxylic acids by their distinctive -COOH functional group - it's like their chemical fingerprint. This group contains both a carbon double-bonded to oxygen and a hydroxyl group attached to the same carbon.
The simplest example is methanoic acid (HCOOH), which you might know as formic acid. It's the same stuff that makes ant bites sting!
Quick Tip: Remember that all carboxylic acids end in "-oic acid" when you're naming them.
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Reacting Carboxylic Acids
Carboxylic acids behave just like other acids you've studied, but they react more slowly because they're weaker. Think of them as the "gentle" acids of the chemistry world.
They follow the same three classic acid reactions you need to remember: with metals , with carbonates , and with alkalis .
These reactions are slower than with strong acids like hydrochloric acid, but they still fizz with carbonates and produce hydrogen gas with metals.
Exam Tip: You'll often get asked to write word equations for these three reactions - practice them!
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Weak Acids
Here's why carboxylic acids react slowly: they're weak acids. This doesn't mean they're rubbish at being acids - it's a specific scientific term!
Strong acids completely split apart (ionise) in water, whilst weak acids only partially ionise. Picture it like this: in a room full of strong acid molecules, they all break apart, but in a room of weak acid molecules, only some of them split up.
The equation shows methanoic acid reversibly forming oxonium ions and methanoate ions. That double arrow (⇌) tells you it's reversible - some molecules break apart whilst others join back together.
Key Point: Equal volumes of strong and weak acids have different H⁺ concentrations - this affects their reaction rates.
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Making Esters
Now for something that smells amazing! When carboxylic acids react with alcohols, they create esters - the compounds responsible for most fruity smells.
This reaction needs sulphuric acid as a catalyst to speed things up. The general equation is simple: carboxylic acid + alcohol ⇌ ester + water.
A classic example is ethanoic acid (vinegar) reacting with methanol to make methyl ethanoate. Notice the reversible arrow again - this reaction can go both ways.
Remember: Water is always formed when making esters - it's a condensation reaction!
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Naming Esters
Naming esters follows a simple two-part rule that'll save you marks in exams. The first part comes from the alcohol, and the second part comes from the acid.
Take propyl ethanoate: "propyl" comes from propanol (the alcohol), and "ethanoate" comes from ethanoic acid. Just swap the "-oic acid" ending for "-oate" when naming the acid part.
Think of it like a surname system - the alcohol gives the first name, the acid gives the family name!
Memory Trick: Alcohol first, acid second - just like "ladies first" but for molecules!
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Properties of Esters
Esters are the superstars of the smell world! They're volatile (evaporate easily at room temperature) and have lovely sweet or fruity smells.
This makes them perfect for perfumes and food flavourings. That artificial banana smell in sweets? That's an ester! Same with many perfumes and fruit-flavoured drinks.
Their volatility means they escape into the air easily, which is exactly what you want for something that needs to reach your nose.
Real-World Connection: Next time you smell artificial fruit flavouring, you're detecting ester molecules!
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The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user