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.
What Causes COPD. Over time, exposure to irritants that damage your lungs and airways can cause chronic obstructive pulmonary disease (COPD), which includes chronic bronchitis and emphysema. The main cause of COPD is smoking, but nonsmokers can get COPD too. Smoking.