Concept four Flashcards
What is a catalyst?
a substance that helps a reaction proceed faster
What is an enzyme?
a type of catalyst found in reactions in living things
What are reactants?
materials at the start of the reaction that help form the product
What are products?
materials produced at the end of the reaction
What are the four factors that can affect the rate of a chemical reaction?
the presence of a catalyst, concentration, temperature, and surface area
Greater concentration, higher temperatures, and a greater surface area mean…
a faster reaction
Lower concentration, colder temperatures, and a smaller surface area mean…
a slower reaction
Products are always…
carbon dioxide and water vapor
What is combustion?
when oxygen reacts with a substance to form a new substance and give off thermal energy (or when things burn)
What is the Law of Conservation of Mass?
“matter cannot be created or destroyed”
What is a closed system?
when no additional material is allowed to enter or leave
What is an open system?
when additional material is allowed to enter or leave
