Ch 12 Chemical Reactions Flashcards
what are reactants
the chemicals that react together during a chemical reaction
what are products
the new substance that is formed from a chemical reaction
what is an exothermic reaction
a reaction that gives out heat. heat energy is given out by the reacting chemicals to the surroundings so that the temperature increases
what is an endothermic reaction
a reaction that takes in heat energy from the surroundings causing a decrease in temperature
give an example of an exothermic reaction
fireworks exploding
give an example of an endothermic reaction
sherbet on your tongue
what is an energy profile diagram
a diagram that shows energy transfers in chemical reactions.
what is the collision theory
before a chemical reaction happens the particles in the reactants must collide with each other
what is the activation energy
the minimum energy needed to start a reaction
what is the rate of reaction
describes how quickly a chemical reaction happens
what three ways can a chemical change be measured
- monitor the production of gas
- monitor the temperature changes during a reaction
- monitor the appearance of the reactants and the products during the reaction
what factors can influence the rate of a chemical reaction
- temperature
- concentration of the reactants
- surface area of the reactants
- adding a catalyst
what is surface area
a measure of how much of a substance is exposed
what is a catalyst
a substance that speeds up the rate of a chemical reaction
what are three ways a gas can be collected
- used for gas that is heavier than air. the gas produced sinks to the bottom of the flask and air is pushed out the top as the flask is filled with gas
- used for gas that is lighter than air. the gas produced moves to the top of the flask and air is pushed out of the flask as it fills with gas
- used for gases that don’t dissolve in water. you will see when the jar is full of the new gas as there will be no water left in the jar
