Chemistry 143 Dr. Caddell Modesto Junior College. Chemical Reactions Key

Transcription

1 Chemical Reactions Key 1.) Combine about 2 ml of 0.1 M calcium chloride with about 2 ml of 0.1 M sodium phosphate. CATEGORY: Double Replacement 3CaCl 2 (aq) + 2Na 3 PO 4 (aq) 6NaCl(aq) + Ca3(PO 4 ) 2 (s) 2.) Add about 3 ml of 0.1M zinc sulfate to a test tube. Drop a small piece of copper into the test tube. CATEGORY: No Reaction 3.) Add about 3 ml of 0.1M copper(ii) sulfate to a test tube. Drop a small piece of zinc into the test tube. CATEGORY: Single Replacement Zn(s) + CuSO 4 (aq) ZnSO4(aq) + Cu(s)

2 4.) Add about a half of a gram of copper (II) hydroxide to a test tube. Heat the test tube over a Bunsen burner. CATEGORY: Decomposition Cu(OH) 2 (s) CuO(s) + H2O(g) 5.) Add about 2 grams of copper(ii) sulfate pentahydrate to a test tube. Heat the test tube over a Bunsen burner. CATEGORY: Decomposition CuSO 4 5H 2 O(s) CuSO4(s) + 5H 2 O(g) 6.) Add about a half gram of anhydrous copper(ii) sulfate to a test tube. Add about 5 10 drops of D.I. water to the test tube. CAUTION! ANHYDROUS COPPER (II) SULFATE IS CORROSIVE!. DO NOT GET IT ON YOUR SKIN! IF IT DOES GET ON YOUR SKIN WASH IT OFF WITH ALOT OF WATER! CATEGORY: Combination CuSO 4 (s) + 5H 2 O(l) CuSO4 5H 2 O(s)

3 7.) Add about 2 ml of 0.1M calcium chloride to a test tube. Next add about 2 ml of 0.1 M sodium carbonate to the same test tube. CATEGORY: Double Replacement CaCl 2 (aq) + Na 2 CO 3 (aq) CaCO3(s) + 2NaCl(aq) 8.) Add about 2 ml of 0.1 M calcium chloride to a test tube. Next add about 2 ml of 0.1M sodium nitrate to the same test tube. CATEGORY: No Reaction 9.) Combine about 2 ml of 6M hydrochloric acid with about 4 ml of 3 M sodium hydroxide. CATEGORY: Double Replacement HCl(aq) + NaOH(aq) NaCl(aq) + H2O(l)

4 10.) Add about 4 ml of 3M sodium hydroxide to a test tube. Next add about 2 ml of 3M sulfuric acid to the same test tube. CATEGORY: Double Replacement 2NaOH(aq) + H 2 SO 4 (aq) Na2SO 4 (aq) + 2H 2 O(l) 11.) Add about 2 ml of 1M sodium carbonate to a test tube. Next add about 2 ml of 3M hydrochloric acid to the same test tube. Two reactions occur, one immediately after the other. CATEGORY: Double Replacement and Decomposition s 2HCl(aq) + Na 2 CO 3 (aq) H 2 CO 3 (aq) + 2NaCl(aq) H 2 CO 3 (aq) H 2 O(l) + CO 2 (g) 12.) Add about 3 ml of 6M hydrochloric acid to a test tube. Next, add a small piece of zinc metal to the test tube. IMMEDIATELY GO TO REACTION 13.) WITH THIS SAME TEST TUBE. CATEGORY: Single Replacement Zn(s) + 2HCl(aq) ZnCl2(aq) + H 2 (g)

5 13.) Using the test tube from reaction 12.) with the reaction still occurring, point the test tube away from you and anyone else. Put a lighted wood splint into the test tube. You should hear a sound. CATEGORY: Combustion (or Combination) 2H 2 (g)+ O 2 (g) 2H2O(g) 14.) In the hood, add about 10 ml of ethanol (C 2 H 5 OH) to an evaporating dish. Ignite the liquid with a match. Once you see the reaction, blow out the flame. CATEGORY: Combustion C 2 H 5 OH + 3O 2 (g) 2CO2(g) + 3H 2 O(g)

6 15.) Add about 7 grams of strontium hydroxide to an Erlenmeyer flask. In the hood, add about 3 grams of ammonium chloride to the same flask. Swirl the flask for a few minutes. Be careful to not bring the flask close to your face. Two reactions occur, one immediately after the other. CATEGORY: Double Replacement followed by Decomposition Sr(OH) 2 (s) + 2NH 4 Cl(s) 2NH4OH(s) + SrCl 2 (s) NH 4 OH(s) NH3(g) + H 2 O(l) 16.) Add about 3 ml of 3% hydrogen peroxide to a test tube. Next add a little potassium iodide to the test tube. Potassium iodide acts as a catalyst here. A catalyst makes a reaction happen faster, but is not involved directly in the reaction (it does not appear as a reactant of product). CATEGORY: Decomposition 2H 2 O 2 (aq) 2H2O(l) + O 2 (g)