The reaction of hydrogen gas (H2) with oxygen gas (O2) is a COMBINATION or SYNTHESIS reaction, because multiple substances combine to form fewer substances. Here, the two gases form one substance, water (H2O):
2H2 + O2 -- > 2H2O
The term used to describe the rapid release of bubbles, or rapid release of a gas from a liquid or a solution is called Effervescence. The bubbling of a solution is due to the escape of a gas which may be from a chemical reaction, as in fermenting liquid, or by coming out of a solution after having been under pressure, as in a carbonated drink. For example; soda, champagne among others.
Nonpolar covalent bonds are chemical bonds where two atoms share a pair of electrons with each other and the electronegativities of the two atoms are equal. An example is methane. It has four carbon-hydrogen single covalent bonds. These bonds are nonpolar because the electrons are shared equally.
