Name: Jonathan
Status: Student
Grade: 9-12
Location: CA
Country: N/A
Date: July 2005
Question:
How do you know if something will dissolve in water, and
how do you know if something will or will not conduct electricity without
actually testing the substance?
Replies:
This is a very involved inquiry to address in detail for several reasons:
The word "dissolve" means different things to different people, as does the
term "conduct". What concentration satisfies the condition "dissolve" and
what conductivity satisfies the condition "conduct"? Metal salts are an
example: MgSO2 (Epsom's salts) would be generally "water soluble" and
"conductive", but BaSO4 is much less soluble and less conductive but it is
a matter of degree. Ethanol is miscible with water in all proportions and
its solutions with water are generally considered to be non-conductive, but
acetic acid (vinegar) is also miscible with water, but its conductivity
varies depending upon the concentration. Properties like "solubility" or
"conductivity" are always a matter of degree not absolutes.
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