Kemijske reakcije so povsod okoli nas - od peke kruha... Show more
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Updated Mar 15, 2026
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Vse o Kemijskih Reakcijah
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Kaj so kemijske reakcije
Verjetno si že opazil, kako se železo pokriva z rjo ali kako se pri peki kruha testo spremeni v hrustljavo skorjico. To so kemijske reakcije - procesi, kjer nastanejo popolnoma nove snovi z drugačnimi lastnostmi.
Za razliko od fizikalnih sprememb (kot je taljenje ledu), se pri kemijskih reakcijah vezi med atomi prekinejo in nastanejo nove. Snov se ne samo spremeni po obliki, ampak postane nekaj popolnoma drugega.
Reaktanti so snovi, ki vstopajo v reakcijo (zapišemo jih na levo stran), produkti pa so nove snovi, ki nastanejo (zapišemo jih na desno). Kemijska enačba je naš način zapisa: REAKTANTI → PRODUKTI.
💡 Pomembno: Atomi se nikoli ne uničijo ali nastanejo na novo - samo se prerazporedijo drugače!
Urejanje kemijskih enačb
Zakon o ohranitvi mase pravi, da mora biti masa reaktantov enaka masi produktov. Zato moramo kemijske enačbe vedno urediti - število atomov vsakega elementa mora biti na obeh straneh enako.
Pri urejanju uporabljamo koeficiente (števila pred formulami). Nikoli ne smeš spreminjati indeksov (malih številk v formulah), ker bi s tem spremenil snov!
Vzemimo primer reakcije vodika in kisika v vodo. Začnemo z H₂ + O₂ → H₂O, vendar to ni urejeno. Na levi imamo 2 atoma kisika, na desni samo 1.
Dodamo koeficient 2 pred vodo: H₂ + O₂ → 2H₂O. Zdaj imamo na desni 4 atome vodika, zato potrebujemo še koeficient 2 pred vodik: 2H₂ + O₂ → 2H₂O. Zdaj se vse ujema!
🔧 Nasvet: Vedno na koncu še enkrat preštej vse atome na obeh straneh.
Energijske spremembe in vrste reakcij
Vsaka kemijska reakcija vključuje energijske spremembe. Eksotermne reakcije sproščajo energijo (sveča gori in se segreje), endotermne reakcije pa jo porabljajo (fotosinteza potrebuje svetlobo).
Poznamo tri glavne tipe reakcij. Sinteza je združevanje - kot gorenje magnezijevega traku: 2Mg + O₂ → 2MgO.
Analiza je razkroj - ena snov razpade na več manjših. Primer je elektroliza vode: 2H₂O → 2H₂ + O₂.
Substitucija je zamenjava - cink zamenja vodik v kislini: Zn + 2HCl → ZnCl₂ + H₂.
⚡ Zanimivost: Rjavenje železa je sinteza, ki poteka počasi, gorenje pa je hitra sinteza!
Praktični primeri reakcij
Rjavenje železa je odličen primer sinteze iz vsakdanjega življenja. Železo reagira s kisikom in nastane železov(III) oksid - rja.
Besedna enačba: železo + kisik → železov(III) oksid. S formulami: Fe + O₂ → Fe₂O₃.
Pri urejanju najprej uredimo kisik (najmanjši skupni večkratnik za 2 in 3 je 6), potem železo. Končna urejena enačba: 4Fe + 3O₂ → 2Fe₂O₃.
Drugi klasičen primer je reakcija sode bikarbone z kisom. To poznajo vsi iz šolskih poskusov! NaHCO₃ + CH₃COOH → CH₃COONa + H₂O + CO₂. Ta enačba je že urejena.
🧪 Preizkusi: Pri tej reakciji nastane CO₂ (mehurčki), kar je jasen znak kemijske reakcije!
Ključne točke za test
Znaki kemijske reakcije so sprememba barve, nastanek plina (mehurčki), nastanek oborine ali sproščanje/poraba toplote. To te loči od fizikalnih sprememb.
Pri urejanju enačb nikoli ne spreminjaj indeksov v formulah - samo koeficiente! Vedno na koncu preveri, če se število vseh atomov ujema na obeh straneh.
Koraki za reševanje nalog: preberi nalogo → zapiši besedno enačbo → zapiši s formulami → uredi s koeficienti → preveri vse atome.
Najpogostejša napaka je, da pozabiš preveriti vse elemente po urejanju. Ne pozabi tudi razlike med reaktanti (levo) in produkti (desno).
📝 Hiter test: Če se spremeni barva, nastanejo mehurčki ali se sprosti toplota - to je kemijska reakcija!
We thought you’d never ask...
What is the Knowunity AI companion?
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.
Where can I download the Knowunity app?
You can download the app in the Google Play Store and in the Apple App Store.
Is Knowunity really free of charge?
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
Most popular content in Naravoslovje
Most popular content
Can't find what you're looking for? Explore other subjects.
Students love us — and so will you.
4.6/5
App Store
4.7/5
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 Knowunity AI. 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 Knowunity AI. 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
Vse o Kemijskih Reakcijah
Kemijske reakcije so povsod okoli nas - od peke kruha do rjavenja kolesa. To je proces, kjer se snovi spremenijo v popolnoma nove snovi z drugačnimi lastnostmi, kar je nekaj popolnoma drugega kot običajno taljenje ali zmrzovanje.
Kaj so kemijske reakcije
Verjetno si že opazil, kako se železo pokriva z rjo ali kako se pri peki kruha testo spremeni v hrustljavo skorjico. To so kemijske reakcije - procesi, kjer nastanejo popolnoma nove snovi z drugačnimi lastnostmi.
Za razliko od fizikalnih sprememb (kot je taljenje ledu), se pri kemijskih reakcijah vezi med atomi prekinejo in nastanejo nove. Snov se ne samo spremeni po obliki, ampak postane nekaj popolnoma drugega.
Reaktanti so snovi, ki vstopajo v reakcijo (zapišemo jih na levo stran), produkti pa so nove snovi, ki nastanejo (zapišemo jih na desno). Kemijska enačba je naš način zapisa: REAKTANTI → PRODUKTI.
💡 Pomembno: Atomi se nikoli ne uničijo ali nastanejo na novo - samo se prerazporedijo drugače!
Sign up to see the contentIt's free!
Access to all documents
Improve your grades
Join milions of students
Urejanje kemijskih enačb
Zakon o ohranitvi mase pravi, da mora biti masa reaktantov enaka masi produktov. Zato moramo kemijske enačbe vedno urediti - število atomov vsakega elementa mora biti na obeh straneh enako.
Pri urejanju uporabljamo koeficiente (števila pred formulami). Nikoli ne smeš spreminjati indeksov (malih številk v formulah), ker bi s tem spremenil snov!
Vzemimo primer reakcije vodika in kisika v vodo. Začnemo z H₂ + O₂ → H₂O, vendar to ni urejeno. Na levi imamo 2 atoma kisika, na desni samo 1.
Dodamo koeficient 2 pred vodo: H₂ + O₂ → 2H₂O. Zdaj imamo na desni 4 atome vodika, zato potrebujemo še koeficient 2 pred vodik: 2H₂ + O₂ → 2H₂O. Zdaj se vse ujema!
🔧 Nasvet: Vedno na koncu še enkrat preštej vse atome na obeh straneh.
Sign up to see the contentIt's free!
Access to all documents
Improve your grades
Join milions of students
Energijske spremembe in vrste reakcij
Vsaka kemijska reakcija vključuje energijske spremembe. Eksotermne reakcije sproščajo energijo (sveča gori in se segreje), endotermne reakcije pa jo porabljajo (fotosinteza potrebuje svetlobo).
Poznamo tri glavne tipe reakcij. Sinteza je združevanje - kot gorenje magnezijevega traku: 2Mg + O₂ → 2MgO.
Analiza je razkroj - ena snov razpade na več manjših. Primer je elektroliza vode: 2H₂O → 2H₂ + O₂.
Substitucija je zamenjava - cink zamenja vodik v kislini: Zn + 2HCl → ZnCl₂ + H₂.
⚡ Zanimivost: Rjavenje železa je sinteza, ki poteka počasi, gorenje pa je hitra sinteza!
Sign up to see the contentIt's free!
Access to all documents
Improve your grades
Join milions of students
Praktični primeri reakcij
Rjavenje železa je odličen primer sinteze iz vsakdanjega življenja. Železo reagira s kisikom in nastane železov(III) oksid - rja.
Besedna enačba: železo + kisik → železov(III) oksid. S formulami: Fe + O₂ → Fe₂O₃.
Pri urejanju najprej uredimo kisik (najmanjši skupni večkratnik za 2 in 3 je 6), potem železo. Končna urejena enačba: 4Fe + 3O₂ → 2Fe₂O₃.
Drugi klasičen primer je reakcija sode bikarbone z kisom. To poznajo vsi iz šolskih poskusov! NaHCO₃ + CH₃COOH → CH₃COONa + H₂O + CO₂. Ta enačba je že urejena.
🧪 Preizkusi: Pri tej reakciji nastane CO₂ (mehurčki), kar je jasen znak kemijske reakcije!
Sign up to see the contentIt's free!
Access to all documents
Improve your grades
Join milions of students
Ključne točke za test
Znaki kemijske reakcije so sprememba barve, nastanek plina (mehurčki), nastanek oborine ali sproščanje/poraba toplote. To te loči od fizikalnih sprememb.
Pri urejanju enačb nikoli ne spreminjaj indeksov v formulah - samo koeficiente! Vedno na koncu preveri, če se število vseh atomov ujema na obeh straneh.
Koraki za reševanje nalog: preberi nalogo → zapiši besedno enačbo → zapiši s formulami → uredi s koeficienti → preveri vse atome.
Najpogostejša napaka je, da pozabiš preveriti vse elemente po urejanju. Ne pozabi tudi razlike med reaktanti (levo) in produkti (desno).
📝 Hiter test: Če se spremeni barva, nastanejo mehurčki ali se sprosti toplota - to je kemijska reakcija!
Sign up to see the contentIt's free!
Access to all documents
Improve your grades
Join milions of students
We thought you’d never ask...
What is the Knowunity AI companion?
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.
Where can I download the Knowunity app?
You can download the app in the Google Play Store and in the Apple App Store.
Is Knowunity really free of charge?
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
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Most popular content in Naravoslovje
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Can't find what you're looking for? Explore other subjects.
Students love us — and so will you.
4.6/5
App Store
4.7/5
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 Knowunity AI. 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 Knowunity AI. 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