I think what you are looking for is a catalyst. A catalyst lowers the energy or activation for a reaction, allowing it to happen faster. During the reaction nothing actually happens to or changes the catalyst.
A chemical change is the change of one or more substances into other substances. A physical change is when the state or shape of matter is changed. In a chemical change molecules are combined or beak apart to form new substances.Rusting iron is an example of a chemical change. crushing a can or tearing paper can be an example of physical change.
A change from one or more substances to another is a chemical change.
I think this refers to catalysts as these are considered not to be changed by a reaction-- sometimes this true when molecules react on the surface of a catalyst bu sometimes the catalyst does get involved in the chemical reaction- but is regenerated.
Yes it is a change of state when the food is being digested. Solid food particles are changed into semisolid type of liquid in the stomach where it is further digested. Food molecules have to be changed into simple units before it can be absorbed into our cells.
Ash and gases
Those substances are called, "Catalysts".
Enzymes are catalysts, substances which help to change other substances without being permanetley changed themselves.
an enzyme is a complex protein that cause a specific chemical change in other substances, without being changed themselves.
Reactants are substances that are changed when they become involved in chemical reactions. Products are the new substances that are formed.
Substances that are changed when they become involved in chemical reactions are called reactants. These reactants are changed into new substances that are called products.
Biological evolution is the process of changes that occur in living beings that can be passed on to their offspring. Chemical evolution is the process of changes that occur in substances. However, scientists have found that these substances have changed to form organic molecules, meaning that they have created life from nonliving substances.
The processes are called chemical reactions.
Enzymatic proteins are proteins, or enzymes, that speed up chemical reactions in the body. These reactions break apart biological molecules without being changed themselves.
Elements cannot be changed into simpler substances by chemical means. To change them into simpler particles, you need nuclear means.
Yes, because the substances can be separated apart physically.
yes, they can be changed by increasing the density of their molecules