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.
Follow-up with an orthopedist (bone doctor) is recommended for all clavicle fractures. How long your collarbone will take to heal depends on: 1  Where the break in the bone is (in middle or at the end of the bone). 2  If the bones are aligned. 3  Your age. 4  Children may heal in 3 to 6 weeks. 5  Adults may need up to 12 weeks.