Oxyhydrogen

High Quality Content by WIKIPEDIA articles! Oxyhydrogen is a mixture of hydrogen (H2) and oxygen (O2) gases, typically in a 2:1 molar ratio, the same proportion as water. This gaseous mixture is used for torches for the processing of refractory materials and was the first gaseous mixture used for welding. In practice a ratio of 4:1 or 5:1 hydrogen:oxygen is required to avoid an oxidizing flame. Oxyhydrogen will combust when brought to its autoignition temperature. For a stoichiometric mixture at normal atmospheric pressure, autoignition occurs at about 570 °C (1065 °F). The minimum energy required to ignite such a mixture with a spark is about 20 microjoules. At normal temperature and pressure, oxyhydrogen can burn when it is between about 4% and 95% hydrogen by volume.