What is Chemical: Definition and 1000 Discussions

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. N

    3D Printer Resin's Chemical Makeup?

    Does anyone know what compounds make up the resin used by resin type 3D printers? I need to know if it could possible react with some hexane, toluene, and other chemical solutions for sure, though I believe the resin to be fairly inert chemically. Thanks PF.
  2. M

    Is Chemical engineering the same as Chemical Technology

    The title is self explanatory. Thank you
  3. P

    What chemical solution to use for cleaning digital camera sensors?

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  4. J

    Which chemical reactions are possible?

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  5. D

    Job dangers associated with chemical engineering

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  6. S

    Enthelpy change for chemical reaction

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  7. L

    Is recognizing beauty a chemical process?

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  8. O

    How to remove the chemical smell from plastic?

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  9. Q

    Is COD Measured in Mol/Litres or mg/L?

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  10. V

    Engineering Do Chemical Engineers get to travel the world?

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  11. H

    What does it mean for a chemical reaction to do work on a battery?

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  12. J

    Determing The Chemical Formula of a Hydrate

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  13. jfizzix

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  14. V

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  15. N

    Exploring Entropy Production in Chemical Processes

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  16. I

    Chemical Equilibrium: Understanding & Equation

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  17. M

    Activity and chemical potential

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  18. D

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  19. N

    Engineering Chemical engineers working for space agencies?

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  20. A

    Engineering Detailed Information on Chemical Engineering

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  21. M

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  22. M

    Engineering Chemical vs. Materials Engineering

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  23. S

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  24. A

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  25. S

    Will a Carbonate React with Carbonic Acid? A Chemical Reaction Explanation

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  26. A

    Aerospace or Chemical Eng. Career Help

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  27. H

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  28. K

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  29. L

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  30. H

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  31. C

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  33. Biosyn

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  34. R

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  35. JJBladester

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  36. C

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  37. A

    What's Left to Discover in Chemical and Thermal Physics?

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  38. alemsalem

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  39. L

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  40. R

    Find Remaining NO Concentration: 2NO + 2H2 → N2 + 2H2O, 0.006M NO, 0.002M H2

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  41. V

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  42. B

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  43. K

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  44. C

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  45. O

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  46. L

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  47. MacLaddy

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  48. I

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  49. R

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  50. W

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