Changes

==Origin==

==Origin==

[https://nordan.daynal.org/wiki/index.php?title=English#ca._1100-1500_.09THE_MIDDLE_ENGLISH_PERIOD Middle English] ''dros'', from [https://nordan.daynal.org/wiki/index.php?title=English#ca._600-1100.09THE_OLD_ENGLISH.2C_OR_ANGLO-SAXON_PERIOD Old English] ''drōs'' dregs

[https://nordan.daynal.org/wiki/index.php?title=English#ca._1100-1500_.09THE_MIDDLE_ENGLISH_PERIOD Middle English] ''dros'', from [https://nordan.daynal.org/wiki/index.php?title=English#ca._600-1100.09THE_OLD_ENGLISH.2C_OR_ANGLO-SAXON_PERIOD Old English] ''drōs'' dregs

*[http://en.wikipedia.org/wiki/12th_century before 12th Century]

*[https://en.wikipedia.org/wiki/12th_century before 12th Century]

The term ''dross'' derives from the Old English word ''dros'', meaning the scum produced when smelting metals. By the 15th century it had come to refer to rubbish in general. Dregs and the geological term ''[http://en.wikipedia.org/wiki/Druse_(geology) druse]'' are also thought to be etymologically related. Metallurgical dross is referenced as a [[metaphor]] for worthless [[material]] in the [[Bible]] and in other religious [[texts]].

The term ''dross'' derives from the Old English word ''dros'', meaning the scum produced when smelting metals. By the 15th century it had come to refer to rubbish in general. Dregs and the geological term ''[https://en.wikipedia.org/wiki/Druse_(geology) druse]'' are also thought to be etymologically related. Metallurgical dross is referenced as a [[metaphor]] for worthless [[material]] in the [[Bible]] and in other religious [[texts]].

==Definitions==

==Definitions==

*1: the scum that forms on the [[surface]] of molten metal

*1: the scum that forms on the [[surface]] of molten metal

*3: something that is base, [[trivial]], or inferior  

*3: something that is base, [[trivial]], or inferior  

==Description==

==Description==

'''Dross''' is a mass of solid [http://en.wikipedia.org/wiki/Impurity impurities] floating on a [http://en.wikipedia.org/wiki/Molten_metal molten metal] or dispersed in the metal, such as in wrought iron. It forms on the surface of low-melting-point metals such as tin, lead, zinc or aluminium or alloys by [http://en.wikipedia.org/wiki/Oxidation oxidation] of the metal(s).

'''Dross''' is a mass of solid [https://en.wikipedia.org/wiki/Impurity impurities] floating on a [https://en.wikipedia.org/wiki/Molten_metal molten metal] or dispersed in the metal, such as in wrought iron. It forms on the surface of low-melting-point metals such as tin, lead, zinc or aluminium or alloys by [https://en.wikipedia.org/wiki/Oxidation oxidation] of the metal(s).

With [http://en.wikipedia.org/wiki/Wrought_iron wrought iron], hammering and later rolling, removed some dross. With tin and lead the dross can be removed by adding [http://en.wikipedia.org/wiki/Sodium_hydroxide sodium hydroxide] pellets, which dissolve the oxides and form a [http://en.wikipedia.org/wiki/Slag slag]. Dross can also be skimmed off.

With [https://en.wikipedia.org/wiki/Wrought_iron wrought iron], hammering and later rolling, removed some dross. With tin and lead the dross can be removed by adding [https://en.wikipedia.org/wiki/Sodium_hydroxide sodium hydroxide] pellets, which dissolve the oxides and form a [https://en.wikipedia.org/wiki/Slag slag]. Dross can also be skimmed off.

Dross, as a [[solid]], is distinguished from slag, which is a [[liquid]]. Dross product is not entirely [[waste]] material; aluminium dross, for example, can be recycled and is used in secondary [http://en.wikipedia.org/wiki/Steelmaking steelmaking] for slag deoxidation.

Dross, as a [[solid]], is distinguished from slag, which is a [[liquid]]. Dross product is not entirely [[waste]] material; aluminium dross, for example, can be recycled and is used in secondary [https://en.wikipedia.org/wiki/Steelmaking steelmaking] for slag deoxidation.

[[Category: Chemistry]]

[[Category: Chemistry]]

[[Category: Physics]]

[[Category: Physics]]