2007-10-04 15:03:18 · 3 answers · asked by SeXxY&SmArT 2 in Science & Mathematics ➔ Chemistry
Pure element (a perfect crystal with no impurities) will be melt at single of temperature. But impurities presence will caused the melting point will not be as sharp. This will also cause the melting point to begin earlier then expected. Instead the solid is made up of different regions, some with more crystal imperfections then others.These impurities can even be water.
2007-10-04 15:42:39 · answer #1 · answered by ikhlas_heart 2 · 0⤊ 1⤋
It really depends on the impurity level you are looking for. If you like to determine the purity level of at least several percent and also know that the impurity dissolves in the solvent, yes, it is then useful. However, if you want to determine the purity level at ppm (parts-per-millium) level, or you have no idea if the impurity may or may not dissolvable in the solvent, or actually you want to know what kind of impurity it is, then, it is not a good idea to use the melting point reduction method.
2007-10-04 15:53:41 · answer #2 · answered by Hahaha 7 · 0⤊ 0⤋
If it is impure the melting point may well be extended rather than sharp.
If you know what the substance is, then you can compare measured melting point with literature value. Impurities will lower the melting point.
2007-10-04 15:36:22 · answer #3 · answered by Mike W 6 · 0⤊ 0⤋