Please explain the reaction between Potassium carbonate and Magnesium

AI Thread Summary
The discussion centers around a YouTube video demonstrating the reaction K2CO3 + Mg = K + C + MgO, raising questions about the displacement of potassium by magnesium. The key point is that the reaction is driven by thermodynamics, particularly the formation of stable magnesium oxide (MgO), which has a high enthalpy of formation and releases significant heat. While the reactivity series is mentioned, it is noted that thermodynamic stability is more critical in predicting the reaction's outcome. Participants clarify that magnesium's tendency to form stable oxides like MgO is what facilitates the reaction, emphasizing the importance of thermodynamic principles over simple reactivity comparisons.
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TL;DR Summary
Why does Mg reduce K2CO3 even though K is higher in the reactivity series
I saw this video on YouTube, ()
which shows a person making potassium with the following reaction

K2CO3 + Mg = K + C + MgO

I just don’t understand how Mg can displace K

I googled the reaction but couldn’t find much info on this reaction. Could someone give the name to this, or explain the chemistry behind it? There is a part where he uses KMnO4 and glycerin to start the reaction.

Thank you for your time.
 
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Haven't watched the whole video, but by the sound of it it is in a way similar to reducing oxides like it is commonly done in thermites.

Reactivity series is just part of the picture, and even not the most important one. What really matters when predicting reaction products is thermodynamics: ΔG = ΔH - TΔS (and sometimes kinetics, but that's not the case here). In this particular case reaction is probably driven by the MgO creation, such oxides are very stable and have very high enthalpy of formation (more or less making them produces a lot of heat).
 
Borek said:
Haven't watched the whole video, but by the sound of it it is in a way similar to reducing oxides like it is commonly done in thermites.

Reactivity series is just part of the picture, and even not the most important one. What really matters when predicting reaction products is thermodynamics: ΔG = ΔH - TΔS (and sometimes kinetics, but that's not the case here). In this particular case reaction is probably driven by the MgO creation, such oxides are very stable and have very high enthalpy of formation (more or less making them produces a lot of heat).
Like always sir, you give a great explanation. Cannot count how many times you’ve helped out. Thank you so much. This was great.
 
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Borek said:
Haven't watched the whole video, but by the sound of it it is in a way similar to reducing oxides like it is commonly done in thermites.

Reactivity series is just part of the picture, and even not the most important one. What really matters when predicting reaction products is thermodynamics: ΔG = ΔH - TΔS (and sometimes kinetics, but that's not the case here). In this particular case reaction is probably driven by the MgO creation, such oxides are very stable and have very high enthalpy of formation (more or less making them produces a lot of heat).
Hello Borek👋, so what you're saying is that the whole reaction is possible is because Mg which is an Alkali earth metal has an affinity to form oxides is that it?
 
Redriq1 said:
Hello Borek👋, so what you're saying is that the whole reaction is possible is because Mg which is an Alkali earth metal has an affinity to form oxides is that it?

More like "high stability of MgO is what drives the reaction".
 
Borek said:
More like "high stability of MgO is what drives the reaction".
Oooohh so since MgO is more stable than K2CO3 it tends to from MgO in this reaction.. Am i right?
 
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