list at least four signs that a chemical reaction has occurred.
list at least four signs that a chemical reaction has occurred.
Answer
Brief Explanations:
Chemical reactions often show distinct signs. Formation of a precipitate means an insoluble solid forms from solution - phase reactants. Evolution of gas is seen when a gaseous product is formed, like bubbles. A color change indicates new substances with different light - absorbing properties are formed. Temperature change (exothermic or endothermic) implies energy is being released or absorbed during the reaction.
Answer:
- Formation of a precipitate
- Evolution of gas
- Color change
- Temperature change