Science Home Product Information Site Map Search Contact Us   Glencoe Online
Quizzes Quiz
Chemical Reactions

Practice Test
  1.As a result of the experiments of Lavoisier, you know that in a chemical reaction the mass of the products __________.  
  a.   is twice as great as the mass of the reactants  
  b.   cannot be predicted based on the mass of the reactants  
  c.   always equals the mass of the reactants  
  d.   is less than the mass of the reactants  
  2.In chemical equations, __________ represent the number of units of each substance.  
  a.   reactants  
  b.   coefficients  
  c.   products  
  d.   precipitates  
  3.A(n) __________ is a substance that speeds up a chemical reaction without being permanently changed itself.  
  a.   catalyst  
  b.   inhibitor  
  c.   exotherm  
  d.   endotherm  
  4.Some elements usually exist in combinations of two atoms. These combinations are called __________ .  
  a.   coefficients  
  b.   ions  
  c.   isotopes  
  d.   diatomic molecules  
  5.Ten grams of mercury(II) oxide react to produce 9.3 g of mercury and oxygen. What is the mass of the oxygen produced?  
  a.   0.7 g  
  b.   1.7 g  
  c.   19.3 g  
  d.   7.0 g  
  6.Why is oxygen written with a subscript 2?  
  a.   Its mass increases by two times as a result of the reaction.  
  b.   There are two times as many oxygen atoms as reactant atoms.  
  c.   It usually exists as a diatomic molecule.  
  d.   Its mass is twice as great as the reactants'.  
  7.An insoluble compound that comes out of solution during a double displacement reaction is called a __________ .  
  a.   catalyst  
  b.   precipitate  
  c.   reactant  
  d.   solvent  
  8.The law of conservation of mass states that __________ .  
  a.   in a chemical reaction, efforts should be made to preserve rare elements without changing them  
  b.   in a chemical reaction, matter is not created or destroyed, but is conserved  
  c.   matter can be created and destroyed but does not change forms  
  d.   in a chemical reaction, the final mass of the products is always greater than the starting mass of the reactants  
  9.The chemical formula for a compound tells __________ .  
  a.   what elements it contains  
  b.   how stable the compound is  
  c.   how electrons are arranged  
  d.   what type of chemical bond it forms  
  10.If electric current passes through water and initiates a decomposition reaction, what are the expected products?  
  a.   hydrogen and oxygen  
  b.   hydrogen peroxide  
  c.   hydrogen oxide  
  d.   oxygen and water  
  11.A change in which one or more substances are converted into new substances is a __________ .  
  a.   nuclear reaction  
  b.   chemical reaction  
  c.   chemical fusion  
  d.   physical change  
  12.What does it mean for a chemical equation to be balanced?  
  a.   The solid products weigh the same as the reactants.  
  b.   The same number of atoms of each element is on both sides of the equation.  
  c.   The number of reactants is equal to the number of products.  
  d.   The reactants and the products are written with the same coefficients.  
  13.Which of the following is a chemical reaction?  
  a.   water evaporating from salt water leaving salt crystals  
  b.   dew forming on grass  
  c.   rust forming on a car body  
  d.   water freezing into ice  
  14.New substances produced by a chemical reaction are __________ .  
  a.   coefficients  
  b.   reactants  
  c.   resultants  
  d.   products  
  15.What type of reaction produces a precipitate?  
  a.   single displacement  
  b.   decomposition  
  c.   synthesis  
  d.   double displacement  
  16.__________ is a way to describe a chemical reaction using chemical formulas and symbols.  
  a.   Synthesis  
  b.   A physical law  
  c.   A chemical equation  
  d.   The law of conservation of matter  
  17.In a __________ reaction, two or more substances combine to form another substance.  
  a.   synthesis  
  b.   double displacement  
  c.   decomposition  
  d.   single displacement  
  18.When iron combines with oxygen and water in the air to form rust, what substance in the reaction is the product?  
  a.   rust  
  b.   oxygen  
  c.   iron  
  d.   water  

McGraw-Hill / Glencoe
The McGraw-Hill Companies