Reactions / Chemical Equations Extra Practice Problems

 

NOTE:  Most of the following balanced equations will be used to answer questions from the Stoichiometry Extra Practice Problems. You may wish to save your answers and refer to them to save time when doing the Stoichiometry Problems, or you may wish to test your speed by redoing them again. 

 

1. Magnesium carbonate decomposes to magnesium oxide and carbon dioxide.  Write the complete, balanced molecular equation for this reaction.

 

2.  Consider the reaction between phosphoric acid (aq) and sodium hydroxide (aq).   a) Classify this reaction.  b) Write the complete, balanced molecular equation for this reaction.  c) Write the complete, balanced net ionic equation for this reaction. 

 

3.  Solid iron(III) hydroxide reacts with sulfuric acid.  a) What type of reaction is this?  b) What are the products of this reaction?  c) Write the complete, balanced molecular equation for this reaction.

 

4.  Two moles of potassium permanganate reacts with 5 moles of oxalic acid and 6 moles of hydrochloric acid to produce 2 moles of manganese(II) chloride, 10 moles of carbon dioxide, 2 moles of potassium chloride, and 8 moles of water.  Write the balanced equation for this reaction.

 

5. Sand consists primarily of silicon dioxide, SiO2. Pure elemental silicon for use in the semiconductor industry can be produced by reaction of sand with elemental carbon at high temperatures. Carbon monoxide gas (CO) is also a product of the reaction. Classify and write the balanced chemical equation for the reaction of silicon dioxide with carbon. 

 

6.  Aluminum metal can react with iron(III) oxide by a single displacement reaction.  a) What are the names and formulas of the products?  b) Write the complete, balanced molecular equation for this reaction.

 

7.  Sodium metal reacts with chlorine gas to form NaCl.  Classify and write the complete, balanced molecular equation for this reaction.

 

8. Write the complete, balanced molecular equation for the reaction between sulfuric acid and aluminum hydroxide solutions.

 

9. Sulfur trioxide reacts with water in air to produce sulfuric acid (a component of acid rain).  Classify this reaction, and write the complete, balanced molecular equation for this reaction.

 

10.  Urea has the formula (NH2)2CO and is used as a fertilizer because it reacts with water to form ammonia and carbon dioxide.  The ammonia provides nitrogen to the plant.  Write the complete, balanced molecular equation for this reaction.

 

11.  Silicon carbide, SiC, is an important abrasive made by the high temperature reaction of SiO2 with carbon.  CO is the other product.  Write the complete, balanced molecular equation for this reaction.

 

12.  Classify and write the complete, balanced molecular equation for this unbalanced reaction:  

KClO3   KCl  +   O2

 

13.  Carbon disulfide combusts to form carbon dioxide and sulfur dioxide as products.  Write the complete, balanced molecular equation for this reaction.

 

14.  You need to make silver chloride from solutions of silver nitrate and sodium chloride.  a) Classify this reaction.  b) Write the complete, balanced molecular equation for this reaction.  c) Write the complete, balanced net ionic equation for this reaction.

 

15.  Hydrogen gas and chlorine gas react to yield HCl gas as the only product.  Classify and write the complete, balanced molecular equation for this reaction.

 

16.  Ethylene chloride, C2H4Cl2, can be prepared by reacting C2H4 with Cl2.  Classify and write the complete, balanced molecular equation for this reaction.

 

17. a) Complete and balance the equation describing the reaction between nitric acid and a solution of potassium bicarbonate.  b) Give the net ionic equation. c)  Classify the reaction.

 

ANSWERS

 

1. MgCO3 (s) MgO (s) + CO2 (g)

 

2. a) Acid-base neutralization reaction, a kind of double replacement reaction    b)  H3PO4 (aq)  + 3 NaOH (aq)   Na3PO4 (aq)  +  3 H2O (l)    c)  H+ (aq)  + OH- (aq)   H2O (l)

 

3. a) Acid-base neutralization reaction, a kind of double replacement reaction   b) Iron(III) sulfate and water  c) 2 Fe(OH)3 (s) +  3 H2SO4 (aq)   Fe2(SO4)3 (aq) + 6 H2O (l)

 

4.  2 KMnO4  + 5 H2C2O4  +  6 HCl    2 MnCl2  +  10 CO2  +  2 KCl  +  8 H2O

 

5.  Single displacement, SiO2 (s) + 2 C (s)   Si (s)  +  2 CO (g)  

 

6.  a) aluminum oxide (Al2O3) and iron metal (Fe)  b) 2 Al  +  Fe2O3  Al2O3 + 2 Fe

 

7.  Synthesis reaction, 2 Na (s)  +  Cl2 (g)    2 NaCl (s)

 

8.  2 Al(OH)3  (aq) + 3 H2SO4  (aq)   Al2(SO4)3  (aq) +  6 H2O (l)

 

9.  Synthesis reaction, SO3 + H2  H2SO4

 

10.  (NH2)2CO + H2O 2 NH3 + CO2

 

11.  SiO2 + 3 C SiC + 2 CO

 

12.  Decomposition reaction,  2 KClO3 (s)     2 KCl (s) +  3 O2 (g)

 

13.  CS2 + 3 O2   CO2 + 2 SO2

 

14.  a) Precipitation reaction, a kind of double replacement reaction    b)  AgNO3 (aq)  +  NaCl  (aq)    AgCl (s)  +  NaNO3 (aq)   c)   Ag+ (aq)  +  Cl- (aq)    AgCl (s)

 

15.  Synthesis, H2  +  Cl2    2 HCl

 

16.  Synthesis, C2H4  +  Cl2  C2H4Cl2

 

17.  a) HNO3 (aq)  +  KHCO3 (aq)   H2O (l)  +  CO2  (g)  +  KNO3 (aq)    b)  H+ (aq)  +  HCO3- (aq)   H2O (l)  +  CO2  (g)   c)  Double displacement reaction