Week Classify the following reaction: CaCO 2 (s)  CaO (s) + CO 2 (g) a.Neutralization b.Synthesis c.Displacement d.Decomposition

A.15 grams B.30 grams C.45 grams D.74 grams 2. During science lab, Mr. Smith's students tested the reactivity of various metals in sulfuric acid. When zinc was added to sulfuric acid, bubbles were produced, a sure sign that a chemical reaction had taken place. Based on the law of conservation of matter, if 30 grams of zinc are added to 45 grams of sulfuric acid to produce just 1 gram of hydrogen gas, how much zinc sulfate would also be produced? The formula for the chemical reaction is as follows: Zn + H 2 SO 4  ZnSO 4 + H 2

3. An unbalanced chemical equation is shown below. __ H 3 BO 3  __ B 2 O 3 + __ H 2 O What are the coefficients of the balanced equation? a.2: 1: 3c. 3: 1: 2 b.2: 2: 3d. 3: 2: 2 4. Aluminum oxide decomposes to produce aluminum plus oxygen gas. Identify the balanced equation for this decomposition reaction. a.Al 2 O 3  2Al + 3O b.Al 2 O 3  2Al + 3O 2 c.2Al 2 O 3  4Al + 3O 2 d.4Al + 3O 2  2Al 2 O 3

5. A balanced chemical equation has equal numbers of atoms of each type on both sides of the equation. This illustrates the principle of A.Conservation of energy B.Conservation of mass C.Action and reaction D.Natural selection 6. Consider the following chemical equation: 3HfCl 3 + Al  3HfCl 2 + AlCl 3 What are the reactants in this equation? A.HfCl 3 and AlCl 3 B.HfCl 3 and Al C.HfCl 2 and Al D.Al and AlCl 3

7. Rust forms by the reaction of iron with oxygen to produce iron oxide. An 88 g iron nail rusted. The rusted nail (iron oxide) had a mass of 102 g. Identify the mass of oxygen that reacted in the rusting of the nail A.14 g B.88 g C.102 g D.200 g 8. The formula for dinitrogen tetraoxide is A.N 3 O 3 B.NO C.N 2 O 2 D.N 2 O 4

9. What are the coefficients that will balance the skeleton equation below? AlCl 3 + NaOH  Al(OH) 3 + NaCl a.1,3,1,3c. 1,1,1,3 b.3,1,3,1d. 1,3,3,1 8. Which of the following is a balanced equation representing the decomposition of lead(IV) oxide? a. PbO 2  Pb + 2O b. PbO 2  Pb + O 2 c. Pb 2 O  2Pb + O d. PbO  Pb + O 2