Biology
Chemistry
AP Chemistry
English
AP English Literature
Chemistry
Dec 2, 2025
275
4 pages
Group 1 elements, known as the alkali metals, are some of the most reactive metals on the periodic... Show more
Alkali metals are the elements in the first column of the periodic table, including lithium, sodium, and potassium. These metals are completely different from what you might expect metals to be like.
They're incredibly reactive and must be stored under oil to prevent them from reacting with air and water. You'll never find these metals just lying around in nature because they react so quickly with their surroundings.
💡 Remember These aren't your typical "strong" metals - they're soft enough to cut with a butter knife!
Alkali metals have some surprising characteristics that make them stand out. They're soft metals that you can literally slice through with a knife - imagine cutting through butter!
These metals have relatively low melting points and low density, which means some of them can actually float on water. When they form compounds, these are typically colourless, unlike the vibrant colours you might see with other metal compounds.
The most important property is that they're very reactive. This reactivity is what makes them so interesting to study and explains why they behave so dramatically in chemical reactions.
💡 Key Point Low density means lithium, sodium, and potassium all float on water - but don't try this at home as the reaction is explosive!
Reactivity increases as you move down Group 1 from lithium to potassium. This happens because of atomic structure - the atoms get larger as you go down the group.
In bigger atoms, the outer shell electron sits further away from the nucleus. Since opposite charges attract, this greater distance means weaker attraction between the positive nucleus and the negative outer electron.
When the attraction is weaker, it's much easier for the atom to lose its outer electron and react. That's why potassium reacts more violently than sodium, which reacts more violently than lithium.
Interestingly, melting and boiling points decrease as you go down the group - the opposite trend to reactivity.
💡 Memory Tip Think "down = more dramatic" - atoms get bigger, reactivity gets stronger, but melting points get lower!
Alkali metals produce spectacular reactions that are perfect for demonstrating chemical principles. Each metal shows the same types of reactions but with increasing intensity.
When heated in air, they glow and produce coloured flames - lithium burns brick red, sodium burns orange, and potassium burns lilac. In chlorine gas, they create white smoke of metal chlorides.
The most famous reactions happen with water. All three metals fizz violently, producing hydrogen gas and metal hydroxides. Sodium and potassium move around on the water surface, and the hydrogen can even catch fire with dramatic purple or orange flames.
Word equation Alkali metal + water → metal hydroxide + hydrogen
💡 Safety Note These reactions are extremely dangerous in real life - only watch demonstrations by trained teachers with proper safety equipment!
Our AI companion is specifically built for the needs of students. Based on the millions of content pieces we have on the platform we can provide truly meaningful and relevant answers to students. But its not only about answers, the companion is even more about guiding students through their daily learning challenges, with personalised study plans, quizzes or content pieces in the chat and 100% personalisation based on the students skills and developments.
You can download the app in the Google Play Store and in the Apple App Store.
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
6
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore the key groups of the periodic table, including Alkali Metals (Group 1), Alkaline Earth Metals (Group 2), Halogens (Group 7), Noble Gases (Group 8), and Transition Metals. This summary highlights their reactivity, electron configurations, and historical development by Dmitri Mendeleev.
ChemistryExplains periodic properties of each of the elements
ChemistryNotes about the history and arrangement of the elements on the periodic table
ChemistryYuther foyd's groundbreaking experiment with gold foil reveals small, positively charged particles and their impact on atomic structure.
ChemistryExplore the fundamentals of atomic structure and the periodic table in this comprehensive summary. Key concepts include atomic composition, isotopes, ions, and the development of the periodic table by Mendeleev and Newlands. Ideal for students preparing for exams, this resource features clear explanations and a simplified mind map for better understanding.
ChemistryNotes describing trends on the periodic table
ChemistryApp Store
Google Play
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
I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️
Thomas R
iOS user
Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades
Brad T
Android user
Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍
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
I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend
Aubrey
iOS user
Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀
Marco B
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 app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!
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
I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️
Thomas R
iOS user
Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades
Brad T
Android user
Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍
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
I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend
Aubrey
iOS user
Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀
Marco B
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 app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!
Paul T
iOS user
Group 1 elements, known as the alkali metals, are some of the most reactive metals on the periodic table. Understanding their properties and reactions is crucial for GCSE chemistry, as they demonstrate clear patterns that help explain atomic structure and... Show more
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Alkali metals are the elements in the first column of the periodic table, including lithium, sodium, and potassium. These metals are completely different from what you might expect metals to be like.
They're incredibly reactive and must be stored under oil to prevent them from reacting with air and water. You'll never find these metals just lying around in nature because they react so quickly with their surroundings.
💡 Remember: These aren't your typical "strong" metals - they're soft enough to cut with a butter knife!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Alkali metals have some surprising characteristics that make them stand out. They're soft metals that you can literally slice through with a knife - imagine cutting through butter!
These metals have relatively low melting points and low density, which means some of them can actually float on water. When they form compounds, these are typically colourless, unlike the vibrant colours you might see with other metal compounds.
The most important property is that they're very reactive. This reactivity is what makes them so interesting to study and explains why they behave so dramatically in chemical reactions.
💡 Key Point: Low density means lithium, sodium, and potassium all float on water - but don't try this at home as the reaction is explosive!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Reactivity increases as you move down Group 1 from lithium to potassium. This happens because of atomic structure - the atoms get larger as you go down the group.
In bigger atoms, the outer shell electron sits further away from the nucleus. Since opposite charges attract, this greater distance means weaker attraction between the positive nucleus and the negative outer electron.
When the attraction is weaker, it's much easier for the atom to lose its outer electron and react. That's why potassium reacts more violently than sodium, which reacts more violently than lithium.
Interestingly, melting and boiling points decrease as you go down the group - the opposite trend to reactivity.
💡 Memory Tip: Think "down = more dramatic" - atoms get bigger, reactivity gets stronger, but melting points get lower!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Alkali metals produce spectacular reactions that are perfect for demonstrating chemical principles. Each metal shows the same types of reactions but with increasing intensity.
When heated in air, they glow and produce coloured flames - lithium burns brick red, sodium burns orange, and potassium burns lilac. In chlorine gas, they create white smoke of metal chlorides.
The most famous reactions happen with water. All three metals fizz violently, producing hydrogen gas and metal hydroxides. Sodium and potassium move around on the water surface, and the hydrogen can even catch fire with dramatic purple or orange flames.
Word equation: Alkali metal + water → metal hydroxide + hydrogen
💡 Safety Note: These reactions are extremely dangerous in real life - only watch demonstrations by trained teachers with proper safety equipment!
Our AI companion is specifically built for the needs of students. Based on the millions of content pieces we have on the platform we can provide truly meaningful and relevant answers to students. But its not only about answers, the companion is even more about guiding students through their daily learning challenges, with personalised study plans, quizzes or content pieces in the chat and 100% personalisation based on the students skills and developments.
You can download the app in the Google Play Store and in the Apple App Store.
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
6
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore the key groups of the periodic table, including Alkali Metals (Group 1), Alkaline Earth Metals (Group 2), Halogens (Group 7), Noble Gases (Group 8), and Transition Metals. This summary highlights their reactivity, electron configurations, and historical development by Dmitri Mendeleev.
ChemistryExplains periodic properties of each of the elements
ChemistryNotes about the history and arrangement of the elements on the periodic table
ChemistryYuther foyd's groundbreaking experiment with gold foil reveals small, positively charged particles and their impact on atomic structure.
ChemistryExplore the fundamentals of atomic structure and the periodic table in this comprehensive summary. Key concepts include atomic composition, isotopes, ions, and the development of the periodic table by Mendeleev and Newlands. Ideal for students preparing for exams, this resource features clear explanations and a simplified mind map for better understanding.
ChemistryNotes describing trends on the periodic table
ChemistryApp Store
Google Play
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
I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️
Thomas R
iOS user
Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades
Brad T
Android user
Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍
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
I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend
Aubrey
iOS user
Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀
Marco B
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 app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!
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
I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️
Thomas R
iOS user
Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades
Brad T
Android user
Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍
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
I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend
Aubrey
iOS user
Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀
Marco B
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 app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!
Paul T
iOS user
