Macro Tab: Part A. Shake some salt into the water. 1. Identify the solute and the solvent: The solute is and the solvent is.

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1 PhET Simulation: Sugar and Salt Solutions Name Period Useful Information Evaporation: You can evaporate all the water and see the solute crystallize above its saturation point. Formula Molar mass (g/mol) Solubility (mol/l) Sodium chloride NaCl C Calcium chloride CaCl C Sodium nitrate NaNO C Sucrose C 12H 22O C Glucose C 6H 12O C Macro Tab: Part A. Shake some salt into the water. 1. Identify the solute and the solvent: The solute is and the solvent is. 2. What happens to the concentration of the solution when you shake salt into the water? Add more salt. 3. Does the concentration of the solution increase, decrease, or stay the same? Explain in terms of solute, solvent, Add water to the container. 4. Does the concentration of the solution increase decrease or stay the same? Explain in terms of solute, solvent, Let some solution out of the container. 5. Does the concentration of the solution increase decrease or stay the same? Explain in terms of solute, solvent, Evaporate some of the solution. 6. Does the concentration of the solution increase decrease or stay the same? Explain in terms of solute, solvent,

2 Reset all: Start over What volume of water is provided in the container? Empty all the salt out of the container (the salt shaker). What is the concentration in moles per liter of the resulting solution? (Hint: check the show values box ) Calculate the number of grams of salt added. Explore the simulation to find a method to double the concentration of the solution. Describe your method to double the concentration of the salt. Explain in terms of solute, solvent, Calculate the amount in grams of salt present when the concentration is doubled. Part B. Shake some sugar into the water. 1. Identify the solute and the solvent. 2. What happens to the concentration of the solution? Add more sugar. 3. Does the concentration of the solution increase decrease or stay the same? Explain in terms of solute, solvent,

3 Add water to the container. 4. Does the concentration of the solution increase decrease or stay the same? Explain in terms of solute, solvent, Let some solution out of the container. 5. Does the concentration of the solution increase decrease or stay the same? Explain in terms of solute, solvent, Evaporate some of the solution. 6. Does the concentration of the solution increase decrease or stay the same? Explain in terms of solute, solvent, Reset all: Start over What volume of water is provided in the container? Empty all the sugar out of the container. What is the concentration in moles per liter of the resulting solution? (Hint: check the show values box ) Calculate the number of grams of sugar added. Explore the simulation to find a method to double the concentration of the solution. Describe your method to double the concentration of the sugar. Explain in terms of solute, solvent, Calculate the amount in grams of sugar present when the concentration is doubled.

4 Part C: Conductivity meter observations Sketch and describe the parts of the conductivity meter: Place the conductivity meter in pure water. Does the light bulb produce light? Add a small amount of salt Does the light bulb produce light? Explore the simulation: Does adding more salt increase the amount of light produced. Describe your observation to answer the question. Reset the simulation Add a small amount of sugar Does the light bulb produce light? Explore the simulation: Does adding more sugar increase the amount of light produced? Compounds that can dissolve in water and produce light when tested with a conductivity meter are said to be electrolytes. Compounds that can dissolve in water and do not produce light when tested with a conductivity meter are said to be non-electrolytes. Identify salt and sugar as electrolytes or non-electrolytes. Micro Tab: 1. List each of the 5 chemicals in the simulation 2. Identify the type of solute, ionic or molecular to which each of 5 chemicals belongs

5 3. If the solution is evaporated slowly, explain what is happening at the point when the concentrations goes up and down? Explain this using the words solute, solvent, dissolving, and crystallizing. 5. Using your text or cite other resources to describe the difference between an ionic and a covalent compound. 6. Why is the periodic table given as an optional display? How could you use your periodic table to predict conductivity of a solution? 7. Draw pictures that would show what the following chemicals would look like on a microscopic scale if dissolved in water- LiF NaNO 3

6 Part C. Water Tab: Sketch and describe how salt dissolves in water, including orientation of the partial charges in the water molecules, and the number and type of particles produced. Sketch and describe how sugar dissolves in water, including orientation of the partial charges in the water molecules, and the number and type of particles produced. What is the main difference between how salt dissolves and how sugar dissolves?