Electrical Conductivity of Water and Solutions
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Name ____________________________________________________ Lab # _________ Date _________ Lab Activity: The Solution Process What happens when water dissolves a substance? How is water able to do this? What type of substances will water dissolve? What types of substances will water not dissolve? These are some of the questions you will investigate in this lab activity. FOLLOW ALL DIRECTIONS AND WEAR GOGGLES AT ALL TIMES! I. When does 4 + 4 ≠ 8? 1. Use only the equipment on the lab table! Record all observations in the table below. 2. Use the graduated cylinder to measure 4.0 ml of water and place the water into one of the small test tubes. Leave this for the next step. 3. Measure out 4.0 ml of the methanol in the graduated cylinder. The methanol is a type of alcohol and this has green food coloring. Then add the 4.0 ml of water from the test tube to the methanol in the graduated cylinder. Stopper the graduated cylinder and shake. 4. Record the volume in the graduated cylinder in the table on back and your description. Then rinse out the graduated cylinder (pour the contents down the sink). 5. Now measure another 4.0 ml of water and place into one of the small test tubes. 6. Measure 4.0 ml of liquid paraffin from the small plastic bottle labeled “PW” into the graduated cylinder. Describe the paraffin in your table. 7. Add the 4.0 ml of water from the test tube to the cylinder. Stopper and shake this. Record the total volume in the table and your description of the two after mixing them. Name ____________________________________________________ Lab # _________ Date _________ Lab Activity: The Solution Process What happens when water dissolves a substance? How is water able to do this? What type of substances will water dissolve? What types of substances will water not dissolve? These are some of the questions you will investigate in this lab activity. FOLLOW ALL DIRECTIONS AND WEAR GOGGLES AT ALL TIMES! I. When does 4 + 4 ≠ 8? 1. Use only the equipment on the lab table! Record all observations in the table below. 2. Use the graduated cylinder to measure 4.0 ml of water and place the water into one of the small test tubes. Leave this for the next step. 3. Measure out 4.0 ml of the methanol in the graduated cylinder. The methanol is a type of alcohol and this has green food coloring. 4. Then add the 4.0 ml of water from the test tube to the methanol in the graduated cylinder. Stopper the graduated cylinder and shake. 5. Record the volume in the graduated cylinder in the table on back and your description. Then rinse out the graduated cylinder (pour the contents down the sink). 6. Now measure another 4.0 ml of water and place into one of the small test tubes. Measure 4.0 ml of liquid paraffin from the small plastic bottle labeled “PW” into the graduated cylinder. Describe the paraffin in your table. 7. Add the 4.0 ml of water from the test tube to the cylinder. Stopper and shake this. Record the total volume in the table and your description of the two after mixing them. 8. DISPOSE OF THE PARRAFIN BY POURING IT INTO THE BEAKER IN THE FUME HOOD. 9. Then record your data of the volumes in the spreadsheet on the computer. Water Description (4.0 ml) Methanol Description (4.0 ml) Volume after mixing (ml) Description after mixing Water Description (4.0 ml) Paraffin Description (4.0 ml) Volume after mixing (ml) Description after mixing II. Questions 1. Examine the class results. What happened to the volume when the water and alcohol were mixed? Did 4 + 4 = 8? 2. Examine the class results. What happened to the volume when the water and paraffin were mixed? Did 4 + 4 = 8? Which was closer to 4 + 4 = 8, the water and methanol or the water and paraffin? Explain why? 8. DISPOSE OF THE PARRAFIN BY POURING IT INTO THE BEAKER IN THE FUME HOOD. 9. Then record your data of the volumes in the spreadsheet on the computer. Water Description (4.0 ml) Water Description (4.0 ml) Methanol Description 4.0 ml) Paraffin Description (4.0 ml) Volume after mixing (ml) Description after mixing Volume after mixing (ml) Description after mixing II. Questions 1. Examine the class results. What happened to the volume when the water and alcohol were mixed? Did 4 + 4 = 8? 2. Examine the class results. What happened to the volume when the water and paraffin were mixed? Did 4 + 4 = 8? Which was closer to 4 + 4 = 8, the water and methanol or the water and paraffin? Explain why. Lab Activity: The Solution Process Part II Name __________________________________________ What happens when water dissolves a substance? How is water able to do this? What type of substances will water dissolve? What types of substances will water not dissolve? These are some of the questions you will investigate in this lab activity. FOLLOW ALL DIRECTIONS AND WEAR GOGGLES AT ALL TIMES! 1. Use only the equipment on the lab table! Record all observations in the table. 2. Use the graduated cylinder to measure 4.0 ml of water and place the water into one of the small test tubes. 3. Measure out A SMALL AMOUNT of copper (II) sulfate [CuSO4] with the blue spatula. Place this in the 4.0 ml of water. Then stopper and shake the test tube. Record your observations in the table then rinse out the test tube. 4. Then add 4.0 ml of water into another test tube. Measure out A SMALL AMOUNT of cobalt (II) chloride [CuCl2] with the blue spatula. Place this in the 4.0 ml of water. Then stopper and shake the test tube. Record your observations in the table. Then rinse out the test tube. 5. Then add 4.0 ml of water into another test tube. Measure out A SMALL AMOUNT of “salol” with the blue spatula. Place this in the 4.0 ml of water. Then stopper and shake the test tube. Record your observations in the table. Then rinse out the test tube INTO THE BEAKER IN THE FUME HOOD! 6. Sit down and complete the table by writing in the other information. 7. Your teacher will then demonstrate the solubility of Iodine (I2) in water and it’s solubility in the paraffin. Also the solubility of the copper (II) sulfate in the paraffin will be shown as well. Record all of your observations in the table. Lab Activity: The Solution Process Part II Name __________________________________________ What happens when water dissolves a substance? How is water able to do this? What type of substances will water dissolve? What types of substances will water not dissolve? These are some of the questions you will investigate in this lab activity. FOLLOW ALL DIRECTIONS AND WEAR GOGGLES AT ALL TIMES! 1. Use only the equipment on the lab table! Record all observations in the table. 2. Use the graduated cylinder to measure 4.0 ml of water and place the water into one of the small test tubes. 3. Measure out A SMALL AMOUNT of copper (II) sulfate [CuSO4] with the blue spatula. Place this in the 4.0 ml of water. Then stopper and shake the test tube. Record your observations in the table then rinse out the test tube. 4. Then add 4.0 ml of water into another test tube. Measure out A SMALL AMOUNT of cobalt (II) chloride [CuCl2] with the blue spatula. Place this in the 4.0 ml of water. Then stopper and shake the test tube. Record your observations in the table. Then rinse out the test tube. 5. Then add 4.0 ml of water into another test tube. Measure out A SMALL AMOUNT of “salol” with the blue spatula. Place this in the 4.0 ml of water. Then stopper and shake the test tube. Record your observations in the table. Then rinse out the test tube INTO THE BEAKER IN THE FUME HOOD! 6. Sit down and complete the table by writing in the other information. 7. Your teacher will then demonstrate the solubility of Iodine (I 2) in water and it’s solubility in the paraffin. Also the solubility of the copper (II) sulfate in the paraffin will be shown as well. Record all of your observations in the table. Part II. Solubility of Solids Solute Formula Describe Solubility in Water Describe Teacher Demo – Solubility in Paraffin Ions (+) and (-) in the Solution Iodine (I2) 1. Which solutes dissolved in water? ________________________________________________ 2. These solutes were “ionic”. Ionic solutes are composed of a metal ion and nonmetal ion or group. Use your Periodic Table to write the ions that are present in each ionic solute in the table. 3. What happened when the paraffin was mixed with water? Does this make a solution? Which was on top and why. 4. Give an example of a water solution you might find at home and two items that are NOT soluble you might find at home. Part II. Solubility of Solids Solute Formula Describe Solubility in Water Describe Teacher Demo – Solubility in Paraffin Ions (+) and (-) in the Solution 1. Which solutes dissolved in water? ________________________________________________ 2. These solutes were “ionic”. Ionic solutes are composed of a metal ion and nonmetal ion or group. Use your Periodic Table to write the ions that are present in each ionic solute in the table. 3. What happened when the paraffin was mixed with water? Does this make a solution? Which was on top and why. 4. Give an example of a water solution you might find at home and two items that are NOT soluble you might find at home. Lab Activity: The Solution Process Part III & IV Name _________________________________________ Some solutes will dissolve in water. Are there methods or factors that can speed this proves? When solutes dissolve in water how do they change the nature of the water? These are some of the questions you will investigate in this activity. 1. Place a sugar cube into 40 ml of tap water. Note the time and set aside. You will record how long it takes for the sugar cube to dissolve alone without any changes. Record all observations in the table. 2. Discuss with your lab partner what you might do to the sugar cube or water to speed the dissolving. Develop at least three methods or factors you can change. Write these ideas in your data table before trying them. 3. Now test each of your ideas. For each trial always use 40 ml of tap water and one sugar cube. Measure the time it takes to totally dissolve the sugar cube. You may rinse the sugar down the sink. 4. When you are done with your trials examine the original sugar cube. Has it totally dissolved? Make a note of this and the time taken if it is totally dissolved. Method of Dissolving one sugar cube in 40 ml of tap water Time 1. Sugar Cube left undisturbed 2. 3. 4. Lab Activity: The Solution Process Part III & IV Name _________________________________________ Some solutes will dissolve in water. Are there methods or factors that can speed this proves? When solutes dissolve in water how do they change the nature of the water? These are some of the questions you will investigate in this activity. 1. Place a sugar cube into 40 ml of tap water. Note the time and set aside. You will record how long it takes for the sugar cube to dissolve alone without any changes. Record all observations in the table. 2. Discuss with your lab partner what you might do to the sugar cube or water to speed the dissolving. Develop at least three methods or factors you can change. Write these ideas in your data table before trying them. 3. Now test each of your ideas. For each trial always use 40 ml of tap water and one sugar cube. Measure the time it takes to totally dissolve the sugar cube. You may rinse the sugar down the sink. 4. When you are done with your trials examine the original sugar cube. Has it totally dissolved? Make a note of this and the time taken if it is totally dissolved. Method of Dissolving one sugar cube in 40 ml of tap water 1. Sugar Cube left undisturbed 2. 3. 4. Time Electrical Conductivity of Water and Solutions Your teacher will demonstrate the conductivity of distilled and of tap water with the light bulb conductivity device. Record whether the conductivity (yes) or (no) in the table. Then your teacher will dissolve different solutes into the distilled water and demonstrate the conductivity. Again record whether the solution conducts (yes) or not (no). Combination Conductivity (yes) or (no) Type of Compound (Ionic or Molecular) 1. Distilled Water 2. Tap Water 3. Salt (NaCl) water 4. Sugar (C6H12O6) water 5. CuSO4 in water 6. CoCl2 in water 7. Methanol (CH3OH) in water 1. What are some methods of speeding the dissolving of a solute into water? 2. Which substances conducted electricity when dissolved? What type of substance (ionic or molecular) was each? These substances are called “electrolytes”. 3. What must water have in it in order to conduct electricity? Why do you need electrolytes in your diet? Electrical Conductivity of Water and Solutions Your teacher will demonstrate the conductivity of distilled and of tap water with the light bulb conductivity device. Record whether the conductivity (yes) or (no) in the table. Then your teacher will dissolve different solutes into the distilled water and demonstrate the conductivity. Again record whether the solution conducts (yes) or not (no). Combination Conductivity (yes) or (no) Type of Compound (Ionic or Molecular) 1. Distilled Water 2. Tap Water 3. Salt (NaCl) water 4. Sugar (C6H12O6) water 5. CuSO4 in water 6. CoCl2 in water 7. Methanol (CH3OH) in water 1. What are some methods of speeding the dissolving of a solute into water? 2. Which substances conducted electricity when dissolved? What type of substance (ionic or molecular) was each? These substances are called “electrolytes”. 3. What must water have in it in order to conduct electricity? Why do you need electrolytes in your diet?
