Chemical Definition and 1000 Threads

A chemical substance is a form of matter having constant chemical composition and characteristic properties. Some references add that chemical substance cannot be separated into its constituent elements by physical separation methods, i.e., without breaking chemical bonds. Chemical substances can be simple substances, chemical compounds, or alloys. Chemical elements may or may not be included in the definition, depending on expert viewpoint.Chemical substances are often called 'pure' to set them apart from mixtures. A common example of a chemical substance is pure water; it has the same properties and the same ratio of hydrogen to oxygen whether it is isolated from a river or made in a laboratory. Other chemical substances commonly encountered in pure form are diamond (carbon), gold, table salt (sodium chloride) and refined sugar (sucrose). However, in practice, no substance is entirely pure, and chemical purity is specified according to the intended use of the chemical.
Chemical substances exist as solids, liquids, gases, or plasma, and may change between these phases of matter with changes in temperature or pressure and time. Chemical substances may be combined or converted to others by means of chemical reactions.
Forms of energy, such as light and heat, are not matter, and are thus not "substances" in this regard.

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  1. H

    Exploring Environmental and Chemical Cleaning Advances

    I need help with the following problems: 1.Are there environmental concerns that arise as a result of the chemical process of cleaning?(if yes go into details) 2. Has the cleaning industry made any recent advances that have chemical foundations(if yes go into details) Websites, Answers...
  2. P

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  3. A

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  4. P

    Are These Chemical Reactions Correctly Balanced?

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  5. J

    Chemical Composition of Slippery Elm Tree Slime

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  6. P

    Chemical engineering employment oppurtunities in the pacific northwest?

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  7. K

    What Is the Chemical Formula and Uses of Vetro Paste?

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  8. S

    Photons and zero chemical potential ?

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  9. P

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  10. R

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  11. S

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  12. S

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  13. S

    Chemical resonance is legitimate and universal

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  14. M

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  15. N

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  16. S

    Can someone simply describe the definition of the chemical potential?

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  17. C

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  18. edward

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  19. S

    Higher Chemical Concentration = Higher Temperature of Precipitation. Why?

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  20. K

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  21. M

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  22. Z

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  23. A

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  24. V

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  25. K

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  26. L

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  27. U

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  28. F

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  29. M

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  34. E

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  35. Ahmed Abdullah

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  37. K

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  38. C

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  39. F

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  40. F

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  41. P

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  43. K

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  45. H

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  46. A

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  47. L

    Understanding Chemical Reactions: From Mg and O2 to CO2 and H2CO3

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  48. L

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  49. Ahmed Abdullah

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  50. B

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