Editing Boiling (section)

=== Nucleate ===
[[File:Boiling water - close up (short shutter speed).ogv|thumb|A video showing water being boiled. As boiling proceeds, more nucleation sites (where bubbles are formed) can be seen.]]
[[Nucleate boiling]] is characterised by the growth of bubbles or pops on a heated surface (heterogeneous nucleation), which rises from discrete points on a surface, whose temperature is only slightly above the temperature of the liquid. In general, the number of [[nucleation]] sites is increased by an increasing surface temperature.

An irregular surface of the boiling vessel (i.e., increased surface roughness) or additives to the fluid (i.e., surfactants and/or [[nanoparticle]]s) facilitate nucleate boiling over a broader temperature range,<ref>{{Cite journal|last1=Doretti|first1=L.|last2=Longo|first2=G. A.|last3=Mancin|first3=S.|last4=Righetti|first4=G.|last5=Weibel|first5=J. A.|date=2017|title=Nanoparticle Deposition During Cu-Water Nanofluid Pool Boiling|journal=Journal of Physics: Conference Series|language=en|volume=923|issue=1|pages=012004|doi=10.1088/1742-6596/923/1/012004|issn=1742-6596|bibcode=2017JPhCS.923a2004D|doi-access=free}}</ref><ref name="sciencedirect.com">{{cite journal|title= Pool boiling of nanofluids: Comprehensive review of existing data and limited new data|journal= International Journal of Heat and Mass Transfer|volume= 52|issue= 23–24|pages= 5339–5347|doi= 10.1016/j.ijheatmasstransfer.2009.06.040|year= 2009|last1= Taylor|first1= Robert A.|last2= Phelan|first2= Patrick E.|bibcode= 2009IJHMT..52.5339T}}</ref><ref>Robert A Taylor, Patrick E Phelan, Todd Otanicar, Ronald J Adrian, Ravi S Prasher, ''[http://digitalcommons.lmu.edu/cgi/viewcontent.cgi?article=1017&context=mech_fac Vapor generation in a nanoparticle liquid suspension using a focused, continuous laser]'', Applied Physics Letters, Volume 95,  Issue 16, 2009</ref> while an exceptionally smooth surface, such as plastic, lends itself to [[superheating]]. Under these conditions, a heated liquid may show [[boiling delay]] and the temperature may go somewhat above the boiling point without boiling.

Homogeneous nucleation, where the bubbles form from the surrounding liquid instead of on a surface, can occur if the liquid is warmer in its center, and cooler at the surfaces of the container. This can be done, for instance, in a microwave oven, which heats the water and not the container.