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• Plutonium was discovered in 1940 at the University of California at ____.

  Berkele
• ____: the starting material or materials for a chemical reaction.

  Reactants
• ____: the substance or substances produced from a chemical reaction.

  Products
• The road that atoms and molecules take to get from starting materials to products is called the ____.

  reaction pathway
• A ____ plots the energy of the reaction—and all of the molecules and atoms involved—versus how far the reaction has progressed, as

  shown on the following page.

  eaction coordinate

  diagram
• Ea represents the ____. Activation energy is the minimum amount of energy needed to start a chemical

  reaction.

  Activation energy
• ∆E represents the ____ in energy.

  Overall
• The reactants pass through a state that is much higher in energy in order to get to

  the products, called the “____.”

  transition state
• – Activation energy is the amount of energy required to get the reaction “over the

  hill,” or to start the reaction by overcoming the ____ barrier.

  energy
• ____ is the field of science that studies the rates of chemical reactions.

  Chemical kinetics
• For a chemical reaction to occur the particles of the ____ must collide with one another.

  Reactants
• For a chemical reaction to occur the particles of the reactants must have enough ____ to start the reaction.

  Energy
• The particles must have the proper ____ to react with eachother in a chemical reaction.

  Orientation
• The frequency of particles colliding with each other successfully and reacting determines

  the reaction rate. This is called ____.

  Collision Theory
• A higher ____ of the reactants increases the number of particles in the same amount of

  space, so it is more likely that particles will run into each other.

  concentration
• ____ is a measure of kinetic energy, or how fast the particles in a substance are

  moving. When particles are moving faster, they are more likely to collide. People

  Temperature
• A ____ is a substance that changes the rate of a reaction without participating it.

  Catalyst
• If you wanted to say what was occurring in the reaction to the left, you would describe it as: “Two mercury oxide molecules decompose into two mercury atoms plus one oxygen gas

  molecule.”: 2HgO (s) g 2Hg (l) + O2 (g)

  TRUE
• ____ (OR COMBINATION) REACTION: a chemical

  reaction in which smaller molecules combine to form a larger one. As shown below,

  two or more reactants (A and B) combine to form a product (AB).

  Synthesis
• SYNTHESIS (OR ____) REACTION: a chemical

  reaction in which smaller molecules combine to form a larger one. As shown below,

  two or more reactants (A and B) combine to form a product (AB).

  Combination