nonpolar covalent bond. (physical chemistry). A bond in which a pair of electrons is distributed or shared equally between two atoms. 1  Facebook.2  Twitter.onpolar covalent bond. (physical chemistry). A bond in which a pair of electrons is distributed or shared equally between two atoms. 1  Facebook.
When is a barrel chest a sign of a disease process? Chronic obstructive pulmonary disease (COPD) is the most common instance in which a barrel chest will occur. In these cases, itâs a sign of the lungs being over-expanded. This is caused by the loss of elasticity and results in the person having hyper-inflated lungs.
Cigarette smoking is the most common irritant that causes COPD. Pipe, cigar, and other types of tobacco smoking can also cause the condition, especially if the smoke is deeply inhaled. Breathing in other fumes and dust over a long period of time may also cause COPD.