Cooking an egg is a set of chemical changes because chemical bonds are broken and new ones are made, resulting in the formation of new substances. In this case many of the bonds broken are those which cause the egg's proteins to be folded into a globular shape. The protein chains unfold and become entangled causing the setting effect. This is often called denaturing. Whether or not a change can be reversed has no bearing on whether it is chemical or physical. This particular change is almost impossible to reverse because of entropy effects but that simply isn't true of all chemical reactions, and there are many physical changes which are hard to reverse.
It could form an ionic bond with Fluorine or Chlorine. (There are many others that it could as well but those are the most basic)
Answer:
this reaction is cellular respiration, the carbon dioxide is part of the products
Explanation:
Answer:
oxygen: it was the result of biological activities. There were such stable continental shelf environments, which were rare in the Archean, developed after 2.5 billion years ago, facilitating the growth of photosynthetic organisms and thus oxygen production.