Free substitution is a rule in some sports that allows players to enter and leave the game for other players many times during the course of the game; and for coaches to bring in and take out players an unlimited number of times.
Sports that allow free substitution
Basketball. Basketball allows unlimited substitution of players at dead balls, such as full times-out, out-of-bounds turnovers and fouls. Players are allowed to go out and come in again many times, unless they are disqualified or ejected. Players are often substituted for, since it is almost physically impossible to play an entire basketball game (40 minutes in most competitions, 48 in the NBA). Substitutions are also made if a player is getting too many personal fouls and is in danger of disqualifying himself.
Gridiron football. Players can be substituted for between every football play. Most college and pro football teams use 11 completely different players on offense and defense. Often, substitution is made depending on the play being run; for example, a team might bring in a fullback or tailback for a rushing play, or several wide receivers for a passing play. There are also major substitutions made for special teams plays such as punting or kicking a field goal. (Historically, this was not the case; gridiron-based codes originally had a one-platoon system in place that required all players to play all phases of the game. The one-platoon system was largely abolished in the 1940s but aspects of it remained in force in college football until the 1960s, at which time total free substitution was implemented.)
A Level Chemistry "Free Radical Substitution of Alkanes"
In this video, we look at free radical substitution of alkanes. First we explore what is meant by a free radical. We then look at the three stages of free radical substitution of alkanes. Finally, we explore the problem with free radical substitution of alkanes.
This video is aimed at the UK A Level Chemistry specifications. Students studying International A Level Chemistry will need to check their specification.
published: 16 Jan 2022
Free radical reactions | Substitution and elimination reactions | Organic chemistry | Khan Academy
Courses on Khan Academy are always 100% free. Start practicing—and saving your progress—now: https://www.khanacademy.org/science/organic-chemistry/substitution-elimination-reactions/free-radical-reaction-alkanes/v/free-radical-reactions
Free radical reactions. Created by Sal Khan.
Watch the next lesson: https://www.khanacademy.org/science/organic-chemistry/substitution-elimination-reactions/sn1-sn2-sal/v/naming-alkyl-halides?utm_source=YT&utm_medium=Desc&utm_campaign=organicchemistry
Organic Chemistry on Khan Academy: Carbon can form covalent bonds with itself and other elements to create a mind-boggling array of structures. In organic chemistry, we will learn about the reactions chemists use to synthesize crazy carbon based structures, as well as the analytical methods to characterize ...
published: 20 Sep 2010
Free Radical Substitution (Ethane and bromine)
An alkane can get fluorinated/chlorinated/brominated by Free Radical Substitution.
Initiation: Break apart the Cl2 with UV light to make free radicals
Propagation: The Cl radical rips an H from the alkane, leaving it as an alkyl free radical. Then the alkyl free radical steals a Cl from another Cl2 molecule, leaving a Cl radical again, and this makes Cl radical a catalyst.
Termination: Two radicals combine to form a non-radical.
published: 04 Dec 2017
Free Radical Substitution Reactions and Mechanisms Explained Simply (A Level)
In this video I will explain free radical substitution reactions at the level of the UK A Level, US AP Chemistry or Scottish Advanced Higher level.
In this video I will explain the synthesis of chloromethane using free radical substitution. We will look at homolytic fission (Homolysis) and go through initiation, propagation and termination steps.
0:00 Introduction
0:38 What is a Radical?
1:22 Keywords
2:01 Initiation
3:54 Propagation
7:37 Termination
9:21 Summary
11:11 Other Reactions
published: 10 Jun 2021
Free-radical Substitution | A level Chemistry
A level Chemistry
Free-Radical Substitution
Alkanes
Halogenoalkanes
Mechanism
Organic Chemistry | Year 1
published: 21 Apr 2020
A Level Chemistry Free Radical Substitution
A Level Chemistry Freed Radical substitution mechanism. Key definitions of free radical and homiletic fission.
published: 09 Jan 2023
Free Radical Substitution - Solutions to Practice Questions
published: 26 Apr 2022
Free radical substitution reactions
'I'm in the middle of a chain reaction!' Oh dear, no singing!!! OK this video does show you how these reactive radicals can be used to make haloalkanes and the problems of them with regards to CFCs and the ozone. Find out how to write these mechanisms using initiation, propagation and termination steps.
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In this session, Educator Harendra Singh will be discussing Free Radical Substitution from Chemistry for NEET 2024. Watch the complete NEET 2024 Conquer Batch to boost your NEET UG Preparations.
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published: 21 Aug 2023
Free Radical Substitution of Alkanes (A-Level Chemistry)
Outlining the free radical substitution of alkanes, covering the mechanism and reaction in full. The formation of free radicals by homolytic fission (initiation step) is explained, along with the chain reaction nature of free radical substitution. An example of of methane with chlorine to form chloromethane is shown, highlighting possible further substitutions to form dichloro, trichloro and tetrachloromethane.
Recap: 00:29
Forming of Free Radicals (Homolytic Fission): 01:37
Mechanism: 03:03
EXAMPLE methane and chlorine: 04:19
Further substitution: 06:25
Summary: 07:43
Page on chemistrystudent.com:
https://www.chemistrystudent.com/alkanes-freeradicalsubstitution.html
Relevant Videos:
Homolytic and Heterolytic Bond Fission https://youtu.be/1QAa02IT7yE
Thank you for watching - if you fo...
In this video, we look at free radical substitution of alkanes. First we explore what is meant by a free radical. We then look at the three stages of free radic...
In this video, we look at free radical substitution of alkanes. First we explore what is meant by a free radical. We then look at the three stages of free radical substitution of alkanes. Finally, we explore the problem with free radical substitution of alkanes.
This video is aimed at the UK A Level Chemistry specifications. Students studying International A Level Chemistry will need to check their specification.
In this video, we look at free radical substitution of alkanes. First we explore what is meant by a free radical. We then look at the three stages of free radical substitution of alkanes. Finally, we explore the problem with free radical substitution of alkanes.
This video is aimed at the UK A Level Chemistry specifications. Students studying International A Level Chemistry will need to check their specification.
Courses on Khan Academy are always 100% free. Start practicing—and saving your progress—now: https://www.khanacademy.org/science/organic-chemistry/substitution-...
Courses on Khan Academy are always 100% free. Start practicing—and saving your progress—now: https://www.khanacademy.org/science/organic-chemistry/substitution-elimination-reactions/free-radical-reaction-alkanes/v/free-radical-reactions
Free radical reactions. Created by Sal Khan.
Watch the next lesson: https://www.khanacademy.org/science/organic-chemistry/substitution-elimination-reactions/sn1-sn2-sal/v/naming-alkyl-halides?utm_source=YT&utm_medium=Desc&utm_campaign=organicchemistry
Organic Chemistry on Khan Academy: Carbon can form covalent bonds with itself and other elements to create a mind-boggling array of structures. In organic chemistry, we will learn about the reactions chemists use to synthesize crazy carbon based structures, as well as the analytical methods to characterize them. We will also think about how those reactions are occurring on a molecular level with reaction mechanisms. Simply put, organic chemistry is like building with molecular Legos. Let's make some beautiful organic molecules!
About Khan Academy: Khan Academy offers practice exercises, instructional videos, and a personalized learning dashboard that empower learners to study at their own pace in and outside of the classroom. We tackle math, science, computer programming, history, art history, economics, and more. Our math missions guide learners from kindergarten to calculus using state-of-the-art, adaptive technology that identifies strengths and learning gaps. We've also partnered with institutions like NASA, The Museum of Modern Art, The California Academy of Sciences, and MIT to offer specialized content.
For free. For everyone. Forever. #YouCanLearnAnything
Subscribe to Khan Academy’s Organic Chemistry channel: https://www.youtube.com/channel/UCNKPjijOc0WEJ7DIV_Vay3g?sub_confirmation=1
Subscribe to Khan Academy: https://www.youtube.com/subscription_center?add_user=khanacademy
Courses on Khan Academy are always 100% free. Start practicing—and saving your progress—now: https://www.khanacademy.org/science/organic-chemistry/substitution-elimination-reactions/free-radical-reaction-alkanes/v/free-radical-reactions
Free radical reactions. Created by Sal Khan.
Watch the next lesson: https://www.khanacademy.org/science/organic-chemistry/substitution-elimination-reactions/sn1-sn2-sal/v/naming-alkyl-halides?utm_source=YT&utm_medium=Desc&utm_campaign=organicchemistry
Organic Chemistry on Khan Academy: Carbon can form covalent bonds with itself and other elements to create a mind-boggling array of structures. In organic chemistry, we will learn about the reactions chemists use to synthesize crazy carbon based structures, as well as the analytical methods to characterize them. We will also think about how those reactions are occurring on a molecular level with reaction mechanisms. Simply put, organic chemistry is like building with molecular Legos. Let's make some beautiful organic molecules!
About Khan Academy: Khan Academy offers practice exercises, instructional videos, and a personalized learning dashboard that empower learners to study at their own pace in and outside of the classroom. We tackle math, science, computer programming, history, art history, economics, and more. Our math missions guide learners from kindergarten to calculus using state-of-the-art, adaptive technology that identifies strengths and learning gaps. We've also partnered with institutions like NASA, The Museum of Modern Art, The California Academy of Sciences, and MIT to offer specialized content.
For free. For everyone. Forever. #YouCanLearnAnything
Subscribe to Khan Academy’s Organic Chemistry channel: https://www.youtube.com/channel/UCNKPjijOc0WEJ7DIV_Vay3g?sub_confirmation=1
Subscribe to Khan Academy: https://www.youtube.com/subscription_center?add_user=khanacademy
An alkane can get fluorinated/chlorinated/brominated by Free Radical Substitution.
Initiation: Break apart the Cl2 with UV light to make free radicals
Propagati...
An alkane can get fluorinated/chlorinated/brominated by Free Radical Substitution.
Initiation: Break apart the Cl2 with UV light to make free radicals
Propagation: The Cl radical rips an H from the alkane, leaving it as an alkyl free radical. Then the alkyl free radical steals a Cl from another Cl2 molecule, leaving a Cl radical again, and this makes Cl radical a catalyst.
Termination: Two radicals combine to form a non-radical.
An alkane can get fluorinated/chlorinated/brominated by Free Radical Substitution.
Initiation: Break apart the Cl2 with UV light to make free radicals
Propagation: The Cl radical rips an H from the alkane, leaving it as an alkyl free radical. Then the alkyl free radical steals a Cl from another Cl2 molecule, leaving a Cl radical again, and this makes Cl radical a catalyst.
Termination: Two radicals combine to form a non-radical.
In this video I will explain free radical substitution reactions at the level of the UK A Level, US AP Chemistry or Scottish Advanced Higher level.
In this vi...
In this video I will explain free radical substitution reactions at the level of the UK A Level, US AP Chemistry or Scottish Advanced Higher level.
In this video I will explain the synthesis of chloromethane using free radical substitution. We will look at homolytic fission (Homolysis) and go through initiation, propagation and termination steps.
0:00 Introduction
0:38 What is a Radical?
1:22 Keywords
2:01 Initiation
3:54 Propagation
7:37 Termination
9:21 Summary
11:11 Other Reactions
In this video I will explain free radical substitution reactions at the level of the UK A Level, US AP Chemistry or Scottish Advanced Higher level.
In this video I will explain the synthesis of chloromethane using free radical substitution. We will look at homolytic fission (Homolysis) and go through initiation, propagation and termination steps.
0:00 Introduction
0:38 What is a Radical?
1:22 Keywords
2:01 Initiation
3:54 Propagation
7:37 Termination
9:21 Summary
11:11 Other Reactions
'I'm in the middle of a chain reaction!' Oh dear, no singing!!! OK this video does show you how these reactive radicals can be used to make haloalkanes and the ...
'I'm in the middle of a chain reaction!' Oh dear, no singing!!! OK this video does show you how these reactive radicals can be used to make haloalkanes and the problems of them with regards to CFCs and the ozone. Find out how to write these mechanisms using initiation, propagation and termination steps.
'I'm in the middle of a chain reaction!' Oh dear, no singing!!! OK this video does show you how these reactive radicals can be used to make haloalkanes and the problems of them with regards to CFCs and the ozone. Find out how to write these mechanisms using initiation, propagation and termination steps.
➤ Chemistry Mind Maps By HSP subscription: https://unacademy.onelink.me/081J/a5qqcivi
➤ All India Mock Test for NEET 2024 - JOIN NOW: https://unacademy.onelink...
➤ Chemistry Mind Maps By HSP subscription: https://unacademy.onelink.me/081J/a5qqcivi
➤ All India Mock Test for NEET 2024 - JOIN NOW: https://unacademy.onelink.me/081J/6is0lkfx
In this session, Educator Harendra Singh will be discussing Free Radical Substitution from Chemistry for NEET 2024. Watch the complete NEET 2024 Conquer Batch to boost your NEET UG Preparations.
➤ *Use Code ''AVENGER'', Unlock FREE Special Classes on our platform, & also Get Exciting off on your Subscription today.
----------------------------------------------------
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In this session, Educator Harendra Singh will be discussing Free Radical Substitution from Chemistry for NEET 2024. Watch the complete NEET 2024 Conquer Batch to boost your NEET UG Preparations.
➤ *Use Code ''AVENGER'', Unlock FREE Special Classes on our platform, & also Get Exciting off on your Subscription today.
----------------------------------------------------
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➤ About the Educator: Top ranks 1 , 3 , 4 , 5, 7, 9, 10 with maximum number students ie mass selections for NEET and IITJEE
➤ Follow Harendra Singh on Unacademy: https://unacademy.com/@hs-8950
➤ Join our Exclusive Telegram Channel for NEET UG - https://t.me/unacademyneetenglish
----------------------------------------------------
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1. Learn from your favourite teacher
2. Dedicated DOUBT sessions
3. One Subscription, Unlimited Access to Live Online Classes and Videos
4. Real-time interaction with best-in-class teachers
5. You can ask doubts in live online classes
6. Limited students in each Class
7. Download the videos & watch them offline
----------------------------------------------------
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➤ Android: https://unacademy.onelink.me/081J/40a
➤ iOS: https://unacademy.onelink.me/081J/a61
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#Free_Radical_Substitution #neet2024 #neetenglish #neetchemistry #neet #hsp
Outlining the free radical substitution of alkanes, covering the mechanism and reaction in full. The formation of free radicals by homolytic fission (initiation...
Outlining the free radical substitution of alkanes, covering the mechanism and reaction in full. The formation of free radicals by homolytic fission (initiation step) is explained, along with the chain reaction nature of free radical substitution. An example of of methane with chlorine to form chloromethane is shown, highlighting possible further substitutions to form dichloro, trichloro and tetrachloromethane.
Recap: 00:29
Forming of Free Radicals (Homolytic Fission): 01:37
Mechanism: 03:03
EXAMPLE methane and chlorine: 04:19
Further substitution: 06:25
Summary: 07:43
Page on chemistrystudent.com:
https://www.chemistrystudent.com/alkanes-freeradicalsubstitution.html
Relevant Videos:
Homolytic and Heterolytic Bond Fission https://youtu.be/1QAa02IT7yE
Thank you for watching - if you found the video useful, please like and subscribe!
Outlining the free radical substitution of alkanes, covering the mechanism and reaction in full. The formation of free radicals by homolytic fission (initiation step) is explained, along with the chain reaction nature of free radical substitution. An example of of methane with chlorine to form chloromethane is shown, highlighting possible further substitutions to form dichloro, trichloro and tetrachloromethane.
Recap: 00:29
Forming of Free Radicals (Homolytic Fission): 01:37
Mechanism: 03:03
EXAMPLE methane and chlorine: 04:19
Further substitution: 06:25
Summary: 07:43
Page on chemistrystudent.com:
https://www.chemistrystudent.com/alkanes-freeradicalsubstitution.html
Relevant Videos:
Homolytic and Heterolytic Bond Fission https://youtu.be/1QAa02IT7yE
Thank you for watching - if you found the video useful, please like and subscribe!
In this video, we look at free radical substitution of alkanes. First we explore what is meant by a free radical. We then look at the three stages of free radical substitution of alkanes. Finally, we explore the problem with free radical substitution of alkanes.
This video is aimed at the UK A Level Chemistry specifications. Students studying International A Level Chemistry will need to check their specification.
Courses on Khan Academy are always 100% free. Start practicing—and saving your progress—now: https://www.khanacademy.org/science/organic-chemistry/substitution-elimination-reactions/free-radical-reaction-alkanes/v/free-radical-reactions
Free radical reactions. Created by Sal Khan.
Watch the next lesson: https://www.khanacademy.org/science/organic-chemistry/substitution-elimination-reactions/sn1-sn2-sal/v/naming-alkyl-halides?utm_source=YT&utm_medium=Desc&utm_campaign=organicchemistry
Organic Chemistry on Khan Academy: Carbon can form covalent bonds with itself and other elements to create a mind-boggling array of structures. In organic chemistry, we will learn about the reactions chemists use to synthesize crazy carbon based structures, as well as the analytical methods to characterize them. We will also think about how those reactions are occurring on a molecular level with reaction mechanisms. Simply put, organic chemistry is like building with molecular Legos. Let's make some beautiful organic molecules!
About Khan Academy: Khan Academy offers practice exercises, instructional videos, and a personalized learning dashboard that empower learners to study at their own pace in and outside of the classroom. We tackle math, science, computer programming, history, art history, economics, and more. Our math missions guide learners from kindergarten to calculus using state-of-the-art, adaptive technology that identifies strengths and learning gaps. We've also partnered with institutions like NASA, The Museum of Modern Art, The California Academy of Sciences, and MIT to offer specialized content.
For free. For everyone. Forever. #YouCanLearnAnything
Subscribe to Khan Academy’s Organic Chemistry channel: https://www.youtube.com/channel/UCNKPjijOc0WEJ7DIV_Vay3g?sub_confirmation=1
Subscribe to Khan Academy: https://www.youtube.com/subscription_center?add_user=khanacademy
An alkane can get fluorinated/chlorinated/brominated by Free Radical Substitution.
Initiation: Break apart the Cl2 with UV light to make free radicals
Propagation: The Cl radical rips an H from the alkane, leaving it as an alkyl free radical. Then the alkyl free radical steals a Cl from another Cl2 molecule, leaving a Cl radical again, and this makes Cl radical a catalyst.
Termination: Two radicals combine to form a non-radical.
In this video I will explain free radical substitution reactions at the level of the UK A Level, US AP Chemistry or Scottish Advanced Higher level.
In this video I will explain the synthesis of chloromethane using free radical substitution. We will look at homolytic fission (Homolysis) and go through initiation, propagation and termination steps.
0:00 Introduction
0:38 What is a Radical?
1:22 Keywords
2:01 Initiation
3:54 Propagation
7:37 Termination
9:21 Summary
11:11 Other Reactions
'I'm in the middle of a chain reaction!' Oh dear, no singing!!! OK this video does show you how these reactive radicals can be used to make haloalkanes and the problems of them with regards to CFCs and the ozone. Find out how to write these mechanisms using initiation, propagation and termination steps.
➤ Chemistry Mind Maps By HSP subscription: https://unacademy.onelink.me/081J/a5qqcivi
➤ All India Mock Test for NEET 2024 - JOIN NOW: https://unacademy.onelink.me/081J/6is0lkfx
In this session, Educator Harendra Singh will be discussing Free Radical Substitution from Chemistry for NEET 2024. Watch the complete NEET 2024 Conquer Batch to boost your NEET UG Preparations.
➤ *Use Code ''AVENGER'', Unlock FREE Special Classes on our platform, & also Get Exciting off on your Subscription today.
----------------------------------------------------
Please fill out the form if you have any doubts regarding the All India Mock Test for NEET 2024:
https://forms.gle/1g9P6bwnMP6PkLK87
➤ About the Educator: Top ranks 1 , 3 , 4 , 5, 7, 9, 10 with maximum number students ie mass selections for NEET and IITJEE
➤ Follow Harendra Singh on Unacademy: https://unacademy.com/@hs-8950
➤ Join our Exclusive Telegram Channel for NEET UG - https://t.me/unacademyneetenglish
----------------------------------------------------
You can enroll to Unacademy Subscription and get the following benefits:
1. Learn from your favourite teacher
2. Dedicated DOUBT sessions
3. One Subscription, Unlimited Access to Live Online Classes and Videos
4. Real-time interaction with best-in-class teachers
5. You can ask doubts in live online classes
6. Limited students in each Class
7. Download the videos & watch them offline
----------------------------------------------------
Download the Unacademy Learning App here:
➤ Android: https://unacademy.onelink.me/081J/40a
➤ iOS: https://unacademy.onelink.me/081J/a61
----------------------------------------------------
If you don’t wish to miss any updates and or latest videos about NEET UG Exams Preparation, subscribe to the channel now. Students who have already subscribed, stay tuned as we will get more strategy and preparations videos and FREE LIVE CLASSES just for you. Feel free to spread the word – share the videos with your friends and classmates.
#Free_Radical_Substitution #neet2024 #neetenglish #neetchemistry #neet #hsp
Outlining the free radical substitution of alkanes, covering the mechanism and reaction in full. The formation of free radicals by homolytic fission (initiation step) is explained, along with the chain reaction nature of free radical substitution. An example of of methane with chlorine to form chloromethane is shown, highlighting possible further substitutions to form dichloro, trichloro and tetrachloromethane.
Recap: 00:29
Forming of Free Radicals (Homolytic Fission): 01:37
Mechanism: 03:03
EXAMPLE methane and chlorine: 04:19
Further substitution: 06:25
Summary: 07:43
Page on chemistrystudent.com:
https://www.chemistrystudent.com/alkanes-freeradicalsubstitution.html
Relevant Videos:
Homolytic and Heterolytic Bond Fission https://youtu.be/1QAa02IT7yE
Thank you for watching - if you found the video useful, please like and subscribe!
Free substitution is a rule in some sports that allows players to enter and leave the game for other players many times during the course of the game; and for coaches to bring in and take out players an unlimited number of times.
Sports that allow free substitution
Basketball. Basketball allows unlimited substitution of players at dead balls, such as full times-out, out-of-bounds turnovers and fouls. Players are allowed to go out and come in again many times, unless they are disqualified or ejected. Players are often substituted for, since it is almost physically impossible to play an entire basketball game (40 minutes in most competitions, 48 in the NBA). Substitutions are also made if a player is getting too many personal fouls and is in danger of disqualifying himself.
Gridiron football. Players can be substituted for between every football play. Most college and pro football teams use 11 completely different players on offense and defense. Often, substitution is made depending on the play being run; for example, a team might bring in a fullback or tailback for a rushing play, or several wide receivers for a passing play. There are also major substitutions made for special teams plays such as punting or kicking a field goal. (Historically, this was not the case; gridiron-based codes originally had a one-platoon system in place that required all players to play all phases of the game. The one-platoon system was largely abolished in the 1940s but aspects of it remained in force in college football until the 1960s, at which time total free substitution was implemented.)