All elements heavier than iron are made by nuclear reactions that consume energy rather than producing it, so the universe that you describe would have no heavy elements.
As a result of the thermonuclear reactions in the Sun the chemical composition is variable.
The chemical composition of reactants is changed.
The universe and the life are largely dominated by chemical reactions; all around us is chemistry.
A physical reaction is were the current substance can be changed in state and then changed back easily to it's previous state, a chemical reaction is the opposite, it is difficult to change it back to its previous state.
Exothermic reactions are chemical rections since these affects the composition and chemical properties of a matter and result in the formation of new substance. Example burning of coal , electrolysis of water.
Subject of chemistry studies are chemical composition, chemical structures, chemical reactions, chemical properties, synthesis of chemicals, etc.
Chemistry is the study of chemical composition and structure of substances, also studying chemical reactions and chemical synthesis, etc.
Chemistry is the study of chemical composition and structure of substances, also studying chemical reactions and chemical synthesis, etc.
Food production involve chemical reactions.
Chemistry is the study of chemical composition and structure of substances, also studying chemical reactions and chemical synthesis, etc.
The chemical composition is changed during this process.
is isponge react with chlorine