It's one of the givens of kinetic molecular theory. It explains why hydrogen gas diffuses faster than carbon dioxide. Thus there is a greater probability that a lighter molecule like hydrogen will be able to cross a given transient empty space faster than a heavier one before the gap, so to speak, closes up.
(<60 kg) for IM injection in the deltoid muscle only if the subcutane-. ous tissue is not bunched and the injection is made at a 90Â° angle; a 1 needle is sufficient in adults weighing 130â152 lbs (60â70 kg);
Diagram showing the deltoid site for intramuscular injection The deltoid muscle site (upper arm) is recommended for use with injections of small volume, usually equal or less than 1 ml, including vaccinations. This site is not recommended for repeated injections, due to its small area, it is difficult to rotate the injection site. To locate the site, palpate the lower edge of the acromion process.