Enter your Sign on user name and password.

Forgot password?
Sign In | Subscribe
Start learning today, and be successful in your academic & professional career. Start Today!
Loading video...
This is a quick preview of the lesson. For full access, please Log In or Sign up.
For more information, please see full course syllabus of Physical Science
  • Discussion

  • Study Guides

  • Practice Questions

  • Download Lecture Slides

  • Table of Contents

  • Related Books & Services

Lecture Comments (6)

0 answers

Post by oak bird on August 8 at 08:58:57 AM

I have the same question: why H2O2 called hydrogen peroxide? Thanks,

1 answer

Last reply by: Professor Ebs
Tue Jan 7, 2014 11:48 PM

Post by Yisrael Harris on January 7, 2014

Aren't other variations possible, such as: A + BC → AB + BC, meaning that BC gives some of its B to A, but keeps some of it?

0 answers

Post by Yisrael Harris on April 25, 2013

Couldn't there also be a triple displacement?

0 answers

Post by Robert Seitter on February 28, 2012

in some cases like that one they use prefixes as -hypo, -ite and -per

0 answers

Post by Larry Bavly on January 29, 2012

What rule was applied to name hydrogen peroxide? I thought the previous lesson teaches me that H2O2 would be dihydrogen dioxide.

Chemical Reactions

  • A chemical reaction is a chemical change when one or more substances changes into new substances due to valence electron interactions.
  • A chemical reaction can be written out as a chemical equation that uses chemical formulas and other symbols.
  • The total mass of the reactants must equal the total mass of the products.
  • A synthesis reaction is when 2 or more substances combine to form one substance
  • A decomposition reaction is when a substance breaks down into 2 or more substances
  • In a single-displacement reaction, one element replaces another element in a compound.
  • In a double-displacement reaction, 2 positive ions in 2 different compounds switch places to form 2 different compounds.
  • In a combustion reaction a substance combines with oxygen and produces heat and light.
  • All chemical reactions absorb or release energy in the form of heat, light, sound or electricity.
  • Activation energy is the energy needed for a reaction to begin.
  • In endergonic reactions, reactants have lower energy than products, activation energy is high.
  • In exergonic reactions, reactants have more energy than products, activation energy is low.
  • Many factors affect the rate of a chemical reaction. The more the atoms interact, the faster the rate of the reaction will be.

Chemical Reactions

When writing a chemical equation, the _______ are on the left side of the reaction arrow and the ______ are on the right side.
In a chemical reaction, is the mass of the products greater than, equal to, or less than the mass of the reactants?
Equal — law of conservation of mass
What is used in a chemical equation to indicate how many units of each compound are present?
A coefficient
Translate the following equation into words: Na(s) + Cl2 (g) → 2NaCl (s)
One unit of solid sodium plus one unit of diatomic chlorine gas yields two units of solid sodium chloride.
What is the goal when you are balancing equations?
To get the same number of atoms on each side of the reaction — To follow the law of conservation of mass to make sure that no atoms are gained or loss in the reaction.
Balance the following equation: CH4 + O2 → CO 2 + H2O
CH4 + 2O2 → CO2 + 2H2O
What are 6 things you can do to increase the rate of a chemical reaction?
Increase the temperature, pressure, or concentration, add a catalyst, increase the surface area of a reactant, or agitate (stir or shake).
In _______ reactions, products have more energy than reactants and in _______ reactions, reactants have more energy than products.
In chemical reactions, how is energy lost or gained?
Heat, light, sound or electricity
Identify the type of the following reaction: H2SO4 + 2 LiOH → Li2SO4 + 2 H2O
Double displacement

*These practice questions are only helpful when you work on them offline on a piece of paper and then use the solution steps function to check your answer.


Chemical Reactions

Lecture Slides are screen-captured images of important points in the lecture. Students can download and print out these lecture slide images to do practice problems as well as take notes while watching the lecture.

  • Intro 0:00
  • Chemical Reactions 0:05
    • Chemical Reactions
    • Chemical Formula Example
    • Reactants and Products
  • Conservation of Mass 4:58
    • The Total Mass of the Reactant Must Equal the Total Mass of the Products
    • Balancing Chemical Equations
  • Balancing Equations 11:12
    • Example 1: Balancing Equations
    • Example 2: Balancing Equations
    • Example 3: Balancing Equations
  • Types of Reactions 19:17
    • Synthesis
    • Decomposition
    • Single-Displacement
    • Double-Displacement
    • Combustion
  • Energy in Chemical Reactions 24:41
    • Chemical Reactions and Activation Energy
    • Endergonic Reactions
    • Exergonic Reactions
  • Rate of Chemical Reactions 29:42
    • Rate of Chemical Reactions Overview
    • Temperature
    • Concentration
    • Agitation
    • Surface Area
    • Pressure
    • Catalysts and Inhibitors
  • Example 1: Translate Into Chemical Equations 34:32
  • Example 2: Law of Conservation of Mass 37:35
  • Example 3: Balance the Following Equations 40:33
  • Example 4: Math Each Equation With the Correct Type of Reaction 44:58
  • Example 5: Exothermic or Endothermic Reaction? 48:21