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);
1 The place to give the injection is in the middle of the V. The hip is a good place for an injection for adults and children older than seven months.  Deltoid Muscle (Upper arm muscle): Completely expose the upper arm. Feel for the bone that goes across the top of the upper arm.