How do chlorofluorocarbons (cfcs) contribute to ozone depletion? a. chlorine atom (cl) breaks apart the ozone molecule b. cfcs build up and block the filtering effects of the ozone layer c. chlorine atom (cl) bonds to the ozone molecule and changes its chemical properties d. breaks off an oxygen atom (o) and attaches it to a hydroxide ion (oh) to form water

The correct answer is a. chlorine atom (Cl) breaks apart the ozone molecule

Ozone is a layer located in the stratosphere of the atmosphere. It protects living organisms from the harmful ultra violet (UV) radiation coming from the sun. Chlorofluorocarbons (CFCs) cause depletion of ozone layer. UV radiation cause release of a chlorine atom from a CFC molecule. The chlorine atom then breaks an ozone molecule by combining with one oxygen atom to form a chlorine monoxide molecule (ClO) and oxygen (O₂) gas. In this way ozone layer get depleted by the action of CFCs.

blood enters the heart through two large veins, the inferior and superior vena cava, emptying oxygen-poor blood from the body into the right atrium of the heart. as the ventricle contracts, blood leaves the heart through the pulmonic valve, into the pulmonary artery and to the lungs where it is oxygenated.