What if Marsh burned Ettmetal?

[Ookla the Stranger]

What if Marsh tried burning Harmonium while compounding healing?  Would It just vaporize when exploding? This was an interesting question asked by one of my friends.

[Quantus]

"it would do something"

 

 

Quote

 

Silasary

If someone is a full Mistborn and is able to use Feruchemical gold... can they safely burn harmonium?

Brandon Sanderson

Oh, okay. This is theoretically possible. 

Silasary

Would it have an effect?

Brandon Sanderson

Yes. It would do something.

Silasary

And I'm going to hopefully ask what that is.

Brandon Sanderson

*gives a RAFO card* You've earned their card.

Emerald City Comic Con 2018 (March 1, 2018)

 

 

 

EDIT:  also, for scale,  it is more explosive than any of the real alkali metals.  This is a video of a Francium bomb explosion, and it's worse than that

Edited May 10, 2022 by Quantus

[Ookla the Stranger]

Thanks!

[Smye]

1 hour ago, Quantus said:

"it would do something"

EDIT:  also, for scale,  it is more explosive than any of the real alkali metals.  This is a video of a Francium bomb explosion, and it's worse than that:

 

Hey @Quantus - Classically trained chemist here: I hate to break it to you, but Francium in water is WAY more tame than that video - the video in question is showing a hydrogen bomb test from the 50's (nuclear, not chemical). It's been passed around a few times as 'FRANCIUM' but is really just clickbait.

In other, frankly far more interesting news about Francium:

1) There's only an estimated 30 g of Francium in the entirety of the earth's crust! It's radioactive and decays so quickly (it's got a half-life of 22 minutes), we've never been able to gather a large enough sample to know what it actually looks like in metallic form.

2) Sodium is actually the most explosive/dangerous of the alkali metals in water (though Potassium is WICKED nasty when it forms oxides and superoxides (then it's a contact explosive). "But Smye!" you exclaim. "I learned in my chemistry class that the elements become more reactive as you move down the periodic table! How can Sodium (or even Potassium) be the most explosive?" 

I'm so glad you asked. You're right that Francium is far more reactive than those lighter elements (though slightly less so than Cesium, thanks to relativistic effects)... BUT, it would produce barely a whimper if a sizeable amount were dropped in water. Why? In the words of Theodore Gray "Reactivity, as the term is used by chemists, does not accurately correlate with the size and spectacle of the resulting explosion.

When an alkali metal is dropped into water, there are two separate stages to the explosion. First, the metal reacts with the water, tearing off and liberating hydrogen gas. Second, and this part doesn't always happen, the heat generated by the first part of the reaction ignites the hydrogen gas, which burns, sometimes explosively, in the surrounding air. It is this secondary hydrogen gas explosion that produces the visible flame above the bowl of water and/or lake, not the initial reaction of the metal with water (which, of course, tends to happen mostly under water).

And it doesn't matter which alkali metal created that hydrogen gas: Hydrogen is hydrogen, regardless of its source. All that matters is how much of it there is when it's lit, and how well it's mixed with air before it's ignited.

Generally speaking, the hydrogen gas explosion contributes more to the overall visible size of the explosion than does the initial metal-water reaction. And this brings into play an important fact: When you go down the periodic table from lithium to cesium, the atomic weight goes up from 6.94 to 132.9. Higher atomic weight means fewer atoms per unit of weight, and the amount of hydrogen gas generated is directly proportional to the number of atoms. So 5 grams of cesium liberates only about one twentieth as much hydrogen as five grams of lithium, and a bit over one sixth as much as 5 grams of sodium.

You might think this would mean lithium gives the biggest hydrogen explosion, but as you can see from [any high school chemistry demo] it reacts so gently that it never gets hot enough to actually set off the hydrogen. And if it did, it's producing gas so slowly that very little would still be close enough to be ignited.

Sodium and potassium are the happy medium: They produce lots of hydrogen gas, and they do it fast enough that it is still around when they get hot enough to ignite it. In fact, sodium often waits just about exactly the right amount of time to allow a large plume of hydrogen to accumulate and mix with oxygen from the air before igniting an almighty bang. In a very real sense the slightly lower rate of reaction of sodium compared to potassium makes it a perfect time fuse, an essential component in any fuel-air bomb."

So, in short, Ettmetal would be more explosive than Sodium - which is still quite terrifying in the right circumstances - but nowhere near atomic bomb level scary.

[Quantus]

11 minutes ago, Smye said:

Hey @Quantus - Classically trained chemist here: I hate to break it to you, but Francium in water is WAY more tame than that video - the video in question is showing a hydrogen bomb test from the 50's (nuclear, not chemical). It's been passed around a few times as 'FRANCIUM' but is really just clickbait.

In other, frankly far more interesting news about Francium:

1) There's only an estimated 30 g of Francium in the entirety of the earth's crust! It's radioactive and decays so quickly (it's got a half-life of 22 minutes), we've never been able to gather a large enough sample to know what it actually looks like in metallic form.

2) Sodium is actually the most explosive/dangerous of the alkali metals in water (though Potassium is WICKED nasty when it forms oxides and superoxides (then it's a contact explosive). "But Smye!" you exclaim. "I learned in my chemistry class that the elements become more reactive as you move down the periodic table! How can Sodium (or even Potassium) be the most explosive?" 

I'm so glad you asked. You're right that Francium is far more reactive than those lighter elements (though slightly less so than Cesium, thanks to relativistic effects)... BUT, it would produce barely a whimper if a sizeable amount were dropped in water. Why? In the words of Theodore Gray "Reactivity, as the term is used by chemists, does not accurately correlate with the size and spectacle of the resulting explosion.

When an alkali metal is dropped into water, there are two separate stages to the explosion. First, the metal reacts with the water, tearing off and liberating hydrogen gas. Second, and this part doesn't always happen, the heat generated by the first part of the reaction ignites the hydrogen gas, which burns, sometimes explosively, in the surrounding air. It is this secondary hydrogen gas explosion that produces the visible flame above the bowl of water and/or lake, not the initial reaction of the metal with water (which, of course, tends to happen mostly under water).

And it doesn't matter which alkali metal created that hydrogen gas: Hydrogen is hydrogen, regardless of its source. All that matters is how much of it there is when it's lit, and how well it's mixed with air before it's ignited.

Generally speaking, the hydrogen gas explosion contributes more to the overall visible size of the explosion than does the initial metal-water reaction. And this brings into play an important fact: When you go down the periodic table from lithium to cesium, the atomic weight goes up from 6.94 to 132.9. Higher atomic weight means fewer atoms per unit of weight, and the amount of hydrogen gas generated is directly proportional to the number of atoms. So 5 grams of cesium liberates only about one twentieth as much hydrogen as five grams of lithium, and a bit over one sixth as much as 5 grams of sodium.

You might think this would mean lithium gives the biggest hydrogen explosion, but as you can see from [any high school chemistry demo] it reacts so gently that it never gets hot enough to actually set off the hydrogen. And if it did, it's producing gas so slowly that very little would still be close enough to be ignited.

Sodium and potassium are the happy medium: They produce lots of hydrogen gas, and they do it fast enough that it is still around when they get hot enough to ignite it. In fact, sodium often waits just about exactly the right amount of time to allow a large plume of hydrogen to accumulate and mix with oxygen from the air before igniting an almighty bang. In a very real sense the slightly lower rate of reaction of sodium compared to potassium makes it a perfect time fuse, an essential component in any fuel-air bomb."

So, in short, Ettmetal would be more explosive than Sodium - which is still quite terrifying in the right circumstances - but nowhere near atomic bomb level scary.

Damn, but that also makes me feel better actually.  I thought it looked exactly like the H-bomb test footage they've used in every movie since Godzilla, but figured Hollywood was the one to get it persistently wrong and had maybe grabbed some less classified test footage to use as a stand-in.  I figured this was some experimental thermobaric bomb or some such with a deceptive scale on film (that couldnt possibly actually be as big as a nuke). 

Teach me to grab the first search result I find....  

I remembered once seeing an old archival video that showed each metal reacting with water in the sequence, showing how each element down the series reacts more and more violently. I wish I could find the one I remember, but all the ones Im seeing on youtube are more modern and only have the readily available (and/or non-radioactive) elements.  

[Smye]

There are a bunch of videos showing "all the alkali metals," but a bunch of them amp up Rubidium, Cesium, and Francium with a smidge of traditional explosives. Brainiac, a BBC show, was perhaps the worst offender here. When Rubidium and Cesium didn't give  them the results they wanted, they simply tossed in they "rigged a bomb in the bottom of the bath and then blew the [rust] out of it." Source.

It's really too bad that science is often overly simplified to the point of being incorrect in attempt to drive a point home and therefore be 'of more educational benefit.' Science is plenty impressive on it's own. For example - while Cesium and water may not be all that explosive... the Cesium Hydroxide solution the reaction produces is so basic (alkaline) that it's largely impractical to use or even store as it rapidly dissolves glass in any significant concentration.

A fairly reliable source of chemistry info for the YouTubing crowd is The Periodic Table of Videos... they even publish corrections videos when they make an error.

Edited May 10, 2022 by Smye
Cosmerification of profanity