catahoula
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HBr from KBR, HCl, MnO2??
I had a test the other day and I didn't do so well. :| One thing we've had that I really didn't understand was how to obtain HBr while you only have
KBr, HCl and MnO2.
A tip was included in the task - if you mix HCl and MnO2, you will receive Cl2 and a manganese salt. I couldn't really catch what kind of manganese
salt am I supposed to get there.
Can someone walk me through this? I'm really confused...
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morsagh
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HBr can be prepared by reaction of HCl with KBr and than cool down solution of HBr and KCl enough to crystallize less soluble KCl. MnO2 is used when
you want to prepare Br2
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MeshPL
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2HCl -electrolysis-> H2 + Cl2
4HCl + 2KBr + MnO2 --> MnCl2 + 2KCl + Br2
H2 + Br2 --> 2HBr
Although the electrolysis part is a bit cheaty.
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OneEyedPyro
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You could add KBr to ~60% H₂SO₄ solution then heat to generate HBr gas, bubble the gas through distilled water in an ice bath and you will get
HBr. When I tried this the liquid in the boiling flask turned deep red obviously indicating elemental bromine but the HBr I produced remained clear.
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