Subjects

Careers

Open the App

Subjects

Discover the Physical and Chemical Properties of Group 1 Alkali Metals and Group 7 Halogens

Open

14

0

K

kkm_

3/8/2023

Chemistry

C4 Predicting & Identifying Reactions & Products: Combined science

Subjects

/

Chemistry

/

The reactivity series

/

Making a reactivity series

Discover the Physical and Chemical Properties of Group 1 Alkali Metals and Group 7 Halogens

Group 1 alkali metals and Group 7 halogens exhibit distinct trends in their physical and chemical properties across the periodic table. Key points include:

  • Alkali metals increase in reactivity down Group 1 due to weaker attraction between outer electrons and nucleus
  • Halogens decrease in reactivity down Group 7 as it becomes harder for larger atoms to gain electrons
  • Both groups show clear trends in physical properties like melting/boiling points and density
  • Characteristic reactions include alkali metals with water and displacement reactions between halogens
...

3/8/2023

482

C4 Reactions and Products 4.1.1 Group 1 Unusual properties need to specify Soft and easy to cut with a knife. (Softer moving down the group.

View

Alkali Metal Reactions with Water

The observations of alkali metals reactions with water become more vigorous down Group 1:

  • Lithium: Floats with some fizzing, produces alkaline solution
  • Sodium: Floats, melts, and moves vigorously across surface
  • Potassium: Floats, splits, explodes with lilac flame
  • Rubidium: Sinks, sparks vigorously, produces flame
  • Caesium: Very explosive, breaks container, produces flame

Example: Rubidium + water → rubidium hydroxide + hydrogen 2Rb ss + 2H₂O ll → 2RbOH aqaq + H₂ gg

Alkali metals also react with oxygen in air to form metal oxides:

4M ss + O₂ gg → 2M₂O ss

Definition: Oxidation reaction - A reaction in which a substance combines with oxygen

C4 Reactions and Products 4.1.1 Group 1 Unusual properties need to specify Soft and easy to cut with a knife. (Softer moving down the group.

View

Group 7 Halogens

The properties of Group 7 elements halogenshalogens include:

  • Non-metallic properties: brittle, dull solids, poor conductors
  • Diatomic molecules with weak intermolecular forces
  • Seven electrons in outermost shell
  • Form covalent bonds and 1- ions halideionshalide ions in reactions

Trends and properties in Group 7 halogens down the periodic table:

  • Colors become darker
  • Reactivity and bleaching effect decrease
  • Density increases
  • Melting and boiling points increase

Vocabulary: Diatomic - Consisting of two atoms

Example: The diatomic halogens are F₂, Cl₂, Br₂, and I₂

C4 Reactions and Products 4.1.1 Group 1 Unusual properties need to specify Soft and easy to cut with a knife. (Softer moving down the group.

View

Halogen Properties and Reactivity

The physical properties of Group 7 elements vary:

  • Fluorine and chlorine: Gases at room temperature
  • Bromine: Liquid at room temperature
  • Iodine and astatine: Solids at room temperature

Chemical properties of Group 7:

  • React with metals to form ionic metal halides
  • React with non-metals to form covalent compounds
  • React with hydrogen to form hydrogen halides

Highlight: Fluorine is the most reactive halogen due to its small size and strong electron-attracting ability.

The trend in reactivity of Group 7 decreases down the group as it becomes harder for larger atoms to gain electrons.

Example: Chlorine can displace bromine from potassium bromide solution, demonstrating its higher reactivity.

C4 Reactions and Products 4.1.1 Group 1 Unusual properties need to specify Soft and easy to cut with a knife. (Softer moving down the group.

View

Halogen Displacement Reactions

Halogen displacement reactions occur when a more reactive halogen displaces a less reactive halogen from an aqueous solution. This demonstrates the trend in reactivity down Group 7.

For example:

  • Chlorine can displace bromine from potassium bromide
  • Chlorine can displace iodine from potassium iodide
  • Bromine can displace iodine from potassium iodide

Definition: Displacement reaction - A reaction where a more reactive element takes the place of a less reactive element in a compound

These reactions provide evidence for the decreasing reactivity trend in Group 7 elements.

C4 Reactions and Products 4.1.1 Group 1 Unusual properties need to specify Soft and easy to cut with a knife. (Softer moving down the group.

View

Group 1 Alkali Metals

The physical properties of alkali metals in Group 1 include being soft, low density, and having relatively low melting and boiling points. They are shiny when freshly cut and good conductors of electricity and heat.

Key chemical properties of Group 1 alkali metals:

  • Form alkaline solutions when reacting with water
  • Have one electron in outermost shell
  • Increase in reactivity down the group
  • Form 1+ ions when reacting
  • Number of electron shells increases down group

Example: The general equation for alkali metals reacting with water is: 2M ss + 2H₂O ll → 2MOH aqaq + H₂ gg

Highlight: Alkali metals must be stored in oil to prevent reaction with oxygen and water vapor in air.

Vocabulary: Alkalinity - The property of being alkaline or basic pHgreaterthan7pH greater than 7

C4 Reactions and Products 4.1.1 Group 1 Unusual properties need to specify Soft and easy to cut with a knife. (Softer moving down the group.

View

Similar Content

Know The reactivity of metals thumbnail

51

1507

10/11

The reactivity of metals

Includes experiments and chemical equations

Know C5 - Chemical Changes thumbnail

8

618

10/11

C5 - Chemical Changes

AQA GCSE CHEMISTRY HIGHER

Know Chemistry- reactivity series thumbnail

2

86

8

Chemistry- reactivity series

Chemistry year 8 unit 3- reactivity series

Can't find what you're looking for? Explore other subjects.

Knowunity is the # 1 ranked education app in five European countries

Knowunity was a featured story by Apple and has consistently topped the app store charts within the education category in Germany, Italy, Poland, Switzerland and United Kingdom. Join Knowunity today and help millions of students around the world.

Ranked #1 Education App

Download in

Google Play

Download in

App Store

Knowunity is the # 1 ranked education app in five European countries

4.9+

Average App Rating

21 M

Students use Knowunity

#1

In Education App Charts in 17 Countries

950 K+

Students uploaded study notes

Still not sure? Look at what your fellow peers are saying...

iOS User

I love this app so much [...] I recommend Knowunity to everyone!!! I went from a C to an A with it :D

Stefan S, iOS User

The application is very simple and well designed. So far I have found what I was looking for :D

SuSSan, iOS User

Love this App ❤️, I use it basically all the time whenever I'm studying

Subjects

Chemistry

The reactivity series

Making a reactivity series

 

Chemistry

•

482

•

Mar 8, 2023

•

7 pages

Discover the Physical and Chemical Properties of Group 1 Alkali Metals and Group 7 Halogens

K

kkm_

@kkm_

Group 1 alkali metals and Group 7 halogens exhibit distinct trends in their physical and chemical properties across the periodic table. Key points include:

  • Alkali metals increase in reactivity down Group 1 due to weaker attraction between outer electrons and... Show more

C4 Reactions and Products 4.1.1 Group 1 Unusual properties need to specify Soft and easy to cut with a knife. (Softer moving down the group.

Sign up to see the contentIt's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

Alkali Metal Reactions with Water

The observations of alkali metals reactions with water become more vigorous down Group 1:

  • Lithium: Floats with some fizzing, produces alkaline solution
  • Sodium: Floats, melts, and moves vigorously across surface
  • Potassium: Floats, splits, explodes with lilac flame
  • Rubidium: Sinks, sparks vigorously, produces flame
  • Caesium: Very explosive, breaks container, produces flame

Example: Rubidium + water → rubidium hydroxide + hydrogen 2Rb ss + 2H₂O ll → 2RbOH aqaq + H₂ gg

Alkali metals also react with oxygen in air to form metal oxides:

4M ss + O₂ gg → 2M₂O ss

Definition: Oxidation reaction - A reaction in which a substance combines with oxygen

C4 Reactions and Products 4.1.1 Group 1 Unusual properties need to specify Soft and easy to cut with a knife. (Softer moving down the group.

Sign up to see the contentIt's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

Group 7 Halogens

The properties of Group 7 elements halogenshalogens include:

  • Non-metallic properties: brittle, dull solids, poor conductors
  • Diatomic molecules with weak intermolecular forces
  • Seven electrons in outermost shell
  • Form covalent bonds and 1- ions halideionshalide ions in reactions

Trends and properties in Group 7 halogens down the periodic table:

  • Colors become darker
  • Reactivity and bleaching effect decrease
  • Density increases
  • Melting and boiling points increase

Vocabulary: Diatomic - Consisting of two atoms

Example: The diatomic halogens are F₂, Cl₂, Br₂, and I₂

C4 Reactions and Products 4.1.1 Group 1 Unusual properties need to specify Soft and easy to cut with a knife. (Softer moving down the group.

Sign up to see the contentIt's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

Halogen Properties and Reactivity

The physical properties of Group 7 elements vary:

  • Fluorine and chlorine: Gases at room temperature
  • Bromine: Liquid at room temperature
  • Iodine and astatine: Solids at room temperature

Chemical properties of Group 7:

  • React with metals to form ionic metal halides
  • React with non-metals to form covalent compounds
  • React with hydrogen to form hydrogen halides

Highlight: Fluorine is the most reactive halogen due to its small size and strong electron-attracting ability.

The trend in reactivity of Group 7 decreases down the group as it becomes harder for larger atoms to gain electrons.

Example: Chlorine can displace bromine from potassium bromide solution, demonstrating its higher reactivity.

C4 Reactions and Products 4.1.1 Group 1 Unusual properties need to specify Soft and easy to cut with a knife. (Softer moving down the group.

Sign up to see the contentIt's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

Halogen Displacement Reactions

Halogen displacement reactions occur when a more reactive halogen displaces a less reactive halogen from an aqueous solution. This demonstrates the trend in reactivity down Group 7.

For example:

  • Chlorine can displace bromine from potassium bromide
  • Chlorine can displace iodine from potassium iodide
  • Bromine can displace iodine from potassium iodide

Definition: Displacement reaction - A reaction where a more reactive element takes the place of a less reactive element in a compound

These reactions provide evidence for the decreasing reactivity trend in Group 7 elements.

C4 Reactions and Products 4.1.1 Group 1 Unusual properties need to specify Soft and easy to cut with a knife. (Softer moving down the group.

Sign up to see the contentIt's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

Group 1 Alkali Metals

The physical properties of alkali metals in Group 1 include being soft, low density, and having relatively low melting and boiling points. They are shiny when freshly cut and good conductors of electricity and heat.

Key chemical properties of Group 1 alkali metals:

  • Form alkaline solutions when reacting with water
  • Have one electron in outermost shell
  • Increase in reactivity down the group
  • Form 1+ ions when reacting
  • Number of electron shells increases down group

Example: The general equation for alkali metals reacting with water is: 2M ss + 2H₂O ll → 2MOH aqaq + H₂ gg

Highlight: Alkali metals must be stored in oil to prevent reaction with oxygen and water vapor in air.

Vocabulary: Alkalinity - The property of being alkaline or basic pHgreaterthan7pH greater than 7

C4 Reactions and Products 4.1.1 Group 1 Unusual properties need to specify Soft and easy to cut with a knife. (Softer moving down the group.

Sign up to see the contentIt's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

C4 Reactions and Products 4.1.1 Group 1 Unusual properties need to specify Soft and easy to cut with a knife. (Softer moving down the group.

Sign up to see the contentIt's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

Can't find what you're looking for? Explore other subjects.

Students love us — and so will you.

4.9/5

App Store

4.8/5

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