Â­. Â­Dry ice is frozen carbon dioxide. A block of dry ice has a surface temperature of -109.3 degrees Fahrenheit (-78.5 degrees C). Dry ice also has the very nice feature of sublimation -- as it breaks down, it turns directly into carbon dioxide gas rather than a liquid.
The time for a broken collarbone to fully heal depends on the severity of the injury. In children, complete healing may take as little as three to six weeks. In adults, six to 16 weeks or more are often necessary for a collarbone to heal solidly.
wikiHow to Heal from a Broken Collar Bone. Your collarbone, also called clavicle, is a long, thin bone near the base of the front of your neck that connects your breastbone (sternum) and your shoulder girdle. Humans have two collarbones: right and left ones.