Physical Science Chapter 19 Study Guide

  1. What is a chemical reaction? 

It occurs when substances change into new substances 



  1. Identify the different types of chemical reaction. 

Synthesis 2H₂ + O₂ → 2H₂O

Decomposition 2H₂O₂ → 2H₂O + O₂

Single replacement Zn + 2HCl → ZnCl₂ + H₂

Double replacement AgNO₃ + NaCl → AgCl + NaNO₃

Combustion  CH₄ + 2O₂ → CO₂ + 2H₂O

  1. What are characteristics of an exothermic reaction? 

It is a chemical reaction that releases heat energy into its surroundings by making the surroundings warmer.

  1. What are characteristics of an endothermic reaction? 

It absorbs heat energy from its surroundings 

  1. Draw an exothermic and endothermic graph.

exo - bigger arch

Endo- mid way 

  1. What factors increase a reaction rate? 

Reactants, increased temperature, increased surface area of solid reactants, and the presence of a catalyst will increase a reaction rate. 


  1. What is Le Chatlier’s Principle?

 The principal states that if a change of condition is applied to a system in equilibrium, the system will shift in a direction that relieves the stress.