Chemical Forums
Chemistry Forums for Students => Physical Chemistry Forum => Topic started by: constant thinker on May 18, 2005, 06:39:43 PM
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I have rephrased this question. The revised version is the 5th post.
I was looking at periodic table and Bi (Bismuth), which is the last element with a stable isotope, has an oxidation number of -3. Bismuth would bond with other metals that have + oxidation numbers. Getting to the point; If it bonded with another metal would it still be called an alloy?
Alloys are metals that are mixed together since most metals won't bond with each other because they both have + oxidation numbers; correct. Bi will bond with say iron though. Is it still called an alloy.
P.S. This question excludes Sn (Tin) and Pb (Lead) because they generally elect to give up there electrons according to a teacher I had.
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i cant understand what you are talking about. Please rephrase.
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alloys are a mixture, hence u dont need bonds.
remember that metals are generally positive ions in a sea of electrons.
hence when metals get together, they dont bond but instead mix together.
if a metal manages to bond, using their own valence electrons, then its no longer an alloy.
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Most alloys are created from metals in their "elemental" form, meaning that all of the constituents have an oxidation number of 0. They are not positive ions in an alloy. An ion implies that there is an excess of an electron (anion) or an electron deficiency (cation). If a steel alloy suddenly had iron change oxidation state (for example rusting), then the structure of the alloy would likely be destroyed and the metal would form either a salt or an oxide depending on what changed the oxidation state.
Don't know if that answers anything.
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Ok. Rephrased what I'm asking is:
Most of the metals don't bond with each other do to their oxidation numbers. Bi has a - oxidation number and the other metals have + ones. This means that they should bond ionically. This excludes lead and tin.
Bismuth can bond to most of the metals ionically. Would you still call it a metal alloy or just a molecule.
Ex.
2Bi + 3Fe --> Bi2Fe3
This reaction could occur theoritically. Would you still call it a metal alloy even though alloys are only metals that have been mixed or is it considered something else.