A liquid becoming a gas. For instance water (liquid) turns into steam (gas).
Answer:
If it takes more energy to break the original bonds than is released when the new bonds are formed, then the net energy of the reaction is negative. This means that energy must be pumped into the system to keep the reaction going. Such reactions are known as endothermic.
Explanation:
they try to ask themselves why certain things happen and they try to make an educated guess of what will happen.
Well you didn’t post any but I’m hoping that either plastic, lead, wood, glass, or paper, are an option.
The correct answer is B. Chewing in the mouth breaks food into small pieces.
Explanation:
In physical changes, substances do not change their chemical composition or properties but only physical features such as this. This occurs during the chewing because the action of chewing only makes food to be broken down in smaller pieces but does not change its identity, composition, or properties. This does not occur once the food is in contact with saliva, the acid in the stomach, etc. because in these cases, the food reacts with other substances and a chemical reaction occurs, which changes food's identity and composition.