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blogfast25
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Quote: Originally posted by clearly_not_atara  | | Quote: | | 'peach', many moons ago, tried to prepare AlCl3 from Al powder in DCM, gassed with dry HCl. No explosion (but no product either...)
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I. If we're talking about the same person I'm pretty sure he eventually succeeded... but the reaction he wanted to use it for turned
out to be impossible. Small world, it is. I no longer have his notes, unfortunately.
But as long as we're bubbling HCl through powdered Al suspended in a solvent...
II. You of all people should know that AlCl3 is a Lewis acid, and NH3 is a Lewis base. What does that mean?
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I. Why: because 'peach was peach' (real life: John)? I never believed that project would work and still don't believe it now. Not
with benzophenone either.
Not at RT, not without a protonic oxidiser.
You'd probably be in trouble if it did:
Al(s) + 3 HCl(g) === > AlCl3(s) + 3/2 H2(g)
... is worth about - 400 kJ/mol at STP, seriously exothermic!
His notes are still on the site, search and yee shall find! 
II. And yet AlCl3 and NH3 don't seem to form a Lewis adduct in these here conditions, they're funny like that
these pesky Lewis acids and bases  . If you have references to the contrary, I'd be
very interested.
[Edited on 8-1-2016 by blogfast25]
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Magpie
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I tried to make PCl3(l) by gassing white P with Cl2. With a standard enthalpy of formation of -320 KJ/mol the reaction was getting out of control and
I decided not to try that again. It can be done however, as demonstrated by garage chemist at versuchschemie.de. This file may be hard to find due
to the administrative problems at versuchschemie.de.
The standard enthalpy of formation for PCl5(s) as calculated from that of its gas and its heat of vaporization is ~ -375 + 65 = -310 KJ/mol. I did
accomplish this with no heat problem whatsoever by dissolving the white P in chloroform then gassing it with Cl2.
The single most important condition for a successful synthesis is good mixing - Nicodem
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blogfast25
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@Magpie:
As far as I know Al doesn't combine with Cl2 when starting at RT (unlike with Br2 or I2). The same holds true for Al
+ HCl: it needs activation energy.
That's why I never believed 'peach' would pull it off (Al + HCl in DCM at RT).
P is notorious for its reactivity in direct union reactions.
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aga
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So .... if one were to be considering the direct route, the Al would need to be Hot then ... hmm ...
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blogfast25
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| Quote: Originally posted by aga |
So .... if one were to be considering the direct route, the Al would need to be Hot then ... hmm ... |
Yes. Heat gently till reaction starts, after initiation it should be self-sustaining...
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