chemical change/chemical reaction
Color Change
Each compound has a characteristic color. When the compound changes during a chemical reaction, the color may change as well. A color change does not always indicate that a chemical change has occurred since there are other factors that can contribute to change in color. An example of a color change due to a chemical reaction is when a half-eaten apple turns brown after it has been exposed to the air.
Temperature Change
Energy is required to break and form chemical bounds. Chemical reactions that involves bond-breaking tend to absorb energy from the surroundings, making the surroundings cooler. Chemical reactions that involves making bonds release energy, which makes the surroundings hotter. An examples of a temperature change in a chemical reaction is when a burning fire fire produces heat.
Chemical Change
In some chemical reactions, atoms combine to form new molecules or or compounds, while other chemical reactions cause atoms to break apart from each other or trade places with another atom.Very often you can't see this exchange of atoms, you must look for changes in physical properties to determine if a chemical reaction has occurred.
Light
When energy is release due to a chemical change it sometimes creates a light source. This type of chemical reactions tends to occur in combustion reactions such as a fire or burning process. Man-made examples of a light being emitted due to a chemical change include fireworks, exploding in the sky and creating a colorful display. Natural examples include fireflies,which use a chemical reaction in their bodies to light.
Gas Bubbles appear
Gas bubbles appear after a chemical reaction has occurred and the mixture becomes saturated with gases.
Volume Change
Each chemical compound has a specific density.If the chemical compound changes due to a chemical reaction , the density changes as well. This causes the volume of the substance to recede or expand during the reaction process. If the volume changes too rapidly, it may cause an explosion. An example of a volume change due to a chemical reaction is when gas bubbles form in magma inside a volcano and expand too rapidly, leading to a volcanic eruption.
Change in Smell or Taste
Each chemical compound has its own distinct smell or taste. If the compound changes after a chemical reaction, the taste or smell of the compound changes as well.An example of this is when fresh food that once smelled delicious slowly spoils and smells rotten. This bad smell sends a warning signal to the brain that tells the person not to eat the food.
Formation of a precipitate
That forms after two solutions are mixed is also a sign of a chemical shape. The precipitate will sometimes fall to the bottom of the container or it may remain suspended in the mixture and make the mixture cloudy. An example of a precipitate formation is when magnesium and calcium oxides mix with water in plumbing and form deposits that clog the pipes.
chemical change
A chemical change takes place when one substance changes into another. These changes are also known as chemical reactions.Chemical changes can be a natural occurrence or man-made. factors that contribute to an chemical change include temperature,concentration of molecules in the substance, the size of the particles in the substance. Although the color,form or other physical characteristics of the substance may change,the total mass of the substance remains constant as started in the law of conversion mass.