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.
By Mayo Clinic Staff. Print. Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory lung disease that causes obstructed airflow from the lungs. Symptoms include breathing difficulty, cough, mucus (sputum) production and wheezing. It's caused by long-term exposure to irritating gases or particulate matter, most often from cigarette smoke. People with COPD are at increased risk of developing heart disease, lung cancer and a variety of other conditions.