Harper College explains that forming a precipitate, color changes, gas formation and temperature change are signs of a chemical change. The University of California, Davis adds that the presence of odor also indicates a chemical change. There are only five indicators of a chemical change.Know More
The University of California, Davis explains the a change in temperature is a clear indicator that a chemical change has occurred. Heat is a product of the reaction and is called an exothermic reaction.
Harper College states that when a gas forms after two substances have been combined, it is clear that a chemical reaction has occurred. The gas is a product of the reaction.
If two chemicals are combined and a new color forms, then a chemical reaction has occurred. Harper College explains that this indicates a chemical change as long as the color change is not a result of a dilution.
The University of California, Davis explains that the presence of an odor indicates a chemical change. For example, when an egg begins to smell, a change in the chemical composition of the egg has occurred.
A precipitate indicates a chemical change. Harper College states that a precipitate forms when two substances react together to form a new substance.Learn more about Chemistry
Cooking can be both a physical and chemical change. For example, mashing up potatoes is a physical change, but baking a cake is a chemical change.Full Answer >
Gasoline burning is an example of a chemical change, because this process produces water vapor and carbon dioxide. For something to be categorized as a chemical change, it must form new chemical substances. It also entails making and breaking molecular bonds. Another example is iron rusting, which forms iron oxide.Full Answer >
Alterations to the electron-based ionic or covalent bonds between ions or atoms happen during a chemical change. Such changes result in one or more new substances with different physical and chemical properties. This type of change stands in contrast to physical changes which, despite sometimes closely resembling chemical changes, only produce a change in physical properties.Full Answer >
Because the process during digestion causes food to become a new substance, digestion is a chemical change. A physical change occurs when a subject changes its shape, size or state.Full Answer >