Editing Ethylene oxide (section)

===Addition of water and alcohols===
Aqueous solutions of ethylene oxide are rather stable and can exist for a long time without any noticeable chemical reaction. However adding a small amount of acid, such as strongly diluted [[sulfuric acid]], immediately leads to the formation of [[ethylene glycol]], even at room temperature:
: (CH<sub>2</sub>CH<sub>2</sub>)O + H<sub>2</sub>O → HO–CH<sub>2</sub>CH<sub>2</sub>–OH

The reaction also occurs in the gas phase, in the presence of a [[phosphoric acid]] salt as a catalyst.<ref name="oe3">{{cite book |chapter=Chapter III. Review of the individual reactions of ethylene oxide |title=Ethylene oxide |editor1=Zimakov, P.V. |editor2=Dyment, O. H. |publisher=Khimiya |year=1967 |pages=90–120}}</ref>

The reaction is usually carried out at about {{convert|60|C|}} with a large excess of water, in order to prevent the reaction of the formed ethylene glycol with ethylene oxide that would form [[diethylene glycol|di-]] and [[triethylene glycol]]:<ref>{{cite web |title=Epoxyethane (Ethylene Oxide) |work=Alkenes menu |publisher=Chemguide |url=https://www.chemguide.co.uk/organicprops/alkenes/epoxyethane.html |access-date=5 October 2009}}</ref>

: 2 (CH<sub>2</sub>CH<sub>2</sub>)O + H<sub>2</sub>O → HO–CH<sub>2</sub>CH<sub>2</sub>–O–CH<sub>2</sub>CH<sub>2</sub>–OH
: 3 (CH<sub>2</sub>CH<sub>2</sub>)O + H<sub>2</sub>O → HO–CH<sub>2</sub>CH<sub>2</sub>–O–CH<sub>2</sub>CH<sub>2</sub>–O–CH<sub>2</sub>CH<sub>2</sub>–OH

The use of alkaline catalysts may lead to the formation of [[polyethylene glycol]]:

: n (CH<sub>2</sub>CH<sub>2</sub>)O + H<sub>2</sub>O → HO–(–CH<sub>2</sub>CH<sub>2</sub>–O–)<sub>n</sub>–H

Reactions with [[alcohol (chemistry)|alcohols]] proceed similarly yielding ethylene glycol ethers:

: (CH<sub>2</sub>CH<sub>2</sub>)O + C<sub>2</sub>H<sub>5</sub>OH → HO–CH<sub>2</sub>CH<sub>2</sub>–OC<sub>2</sub>H<sub>5</sub>

: 2 (CH<sub>2</sub>CH<sub>2</sub>)O + C<sub>2</sub>H<sub>5</sub>OH → HO–CH<sub>2</sub>CH<sub>2</sub>–O–CH<sub>2</sub>CH<sub>2</sub>–OC<sub>2</sub>H<sub>5</sub>

Reactions with lower alcohols occur less actively than with water and require more severe conditions, such as heating to {{convert|160|C|}} and pressurizing to {{convert|3|MPa||abbr=on}} and adding an acid or alkali catalyst.

Reactions of ethylene oxide with fatty alcohols proceed in the presence of [[sodium]] metal, [[sodium hydroxide]], or [[boron trifluoride]] and are used for the synthesis of [[surfactants]].<ref name="oe3"/>