880 likes | 900 Views
Toxins Unit. Investigation I: Dissolving Toxins. Lesson 1: Lethal Dose. Lesson 2: Bearly Alive. Lesson 3: Mixing It Up!. Lesson 4: Weighing In. Lesson 5: Finding Solutions. Lesson 6: Holey Moley. Lesson 7: Is It Toxic?. Toxins Unit – Investigation I. Lesson 1: Lethal Dose.
E N D
Toxins Unit Investigation I: Dissolving Toxins Lesson 1: Lethal Dose Lesson 2: Bearly Alive Lesson 3: Mixing It Up! Lesson 4: Weighing In Lesson 5: Finding Solutions Lesson 6: Holey Moley Lesson 7: Is It Toxic?
Toxins Unit – Investigation I Lesson 1: Lethal Dose
ChemCatalyst • Which substance do you think is most toxic to you – alcohol (ethanol, C2H6O), aspirin (salicylic acid, C7H6O3), or arsenic (As)? Explain your thinking. • How do you think toxicity is determined? Unit IV • Investigation I-X
The Big Question • How is the toxicity of a substance measured and described? Unit IV • Investigation I-X
You will be able to: • Calculate the toxicity of substances based on the lethal dose. Unit IV • Investigation I-X
Notes • Lethal dose (LD50) is the amount of an ingested substance that kills 50 percent of a test sample. It is expressed in mg/kg, or milligrams of substance per kilogram of body weight. Unit IV • Investigation I-X
Activity • Purpose: In this activity you will compare the toxicity of various substances. Unit IV • Investigation I-X
Making Sense • How is dosage related to toxicity? Unit IV • Investigation I-X
Check-In • Methadone is a medication used as a painkiller and as a treatment for those recovering from heroin addiction. The LD50 for methadone is 95 mg/kg. • Would you consider methadone to be more or less toxic than acetaminophen (LD50 = 2404 mg/kg) or aspirin (LD50 = 200 mg/kg)? • Explain how you would calculate the amount of this substance that would be lethal to a 120-pound human. Unit IV • Investigation I-X
Wrap-Up • Toxicity is relative to dosage: The toxicity (or therapeutic effect) of a substance depends on the dose in which it is received. • The lethal dose (or therapeutic dose) of a substance is often expressed as a ratio between a certain mass of the substance and one kilogram of the body weight of an organism exposed to the substance. Unit IV • Investigation I-X
Toxins Unit – Investigation I Lesson 2: Bearly Alive
ChemCatalyst • Drinking water in our homes contains low concentrations of dissolved chlorine, a highly toxic substance. Why can we drink the water? • What do you think concentration means? Unit IV • Investigation I-X
The Big Question • What are the components of solutions, and how are the concentrations of solutions described? Unit IV • Investigation I-X
You will be able to: • Identify the components of solutions and explain their relationship to the concept of solution concentration. Unit IV • Investigation I-X
Notes • A solution is a mixture of two or more substances that is uniform throughout. The substance in the greatest amount is called the solvent. The solute is dissolved in the solvent. • Concentration is the amount of solute for a specified amount of solvent. A common measure of concentration is moles per L, moles/L, which is referred to as molarity, M. Unit IV • Investigation I-X
Activity • Purpose: This activity introduces you to solution chemistry and allows you to examine solutions of differing concentrations. (cont.) Unit IV • Investigation I-X
Making Sense • What do you think is happening in this activity? Write a paragraph explaining your ideas. Include your answers to the following questions: • What causes the size of the gummy bears to change? • Why are the gummy bears in the sugar solutions ranked the way they are? (cont.) Unit IV • Investigation I-X
(cont.) • Why are the gummy bears in the salt solutions different sizes than the gummy bears in the sugar solutions of the same concentration? (cont.) Unit IV • Investigation I-X
(cont.) • The movement of substances from an area of high concentration to an area of lower concentration is called diffusion. Unit IV • Investigation I-X
Check-In • What would happen if you placed a gummy bear in a 1.5 M sugar solution overnight? Use your data table to help you determine the outcome. Draw a picture showing which molecules are moving. Explain your answer in terms of diffusion of water into or out of the bear. Unit IV • Investigation I-X
Wrap-Up • A solution is a mixture that is uniform throughout. The substance in the greatest amount is the solvent. The substance that is dissolved is the solute. • Molarity tells us how many particles or molecules are in solution. Molarity is a measure of the concentration of a solution. (cont.) Unit IV • Investigation I-X
(cont.) • Diffusion is defined as the movement of molecules from an area of higher concentration of that molecule to an area of lower concentration of that molecule. • Salts dissolve in water to give two (or more) ions. Molecular substances do not dissociate; they remain intact as individual molecules. Unit IV • Investigation I-X
Toxins Unit – Investigation I Lesson 3: Mixing It Up!
ChemCatalyst • List three things that dissolve in water. • List three things that do not dissolve in water. Unit IV • Investigation I-X
The Big Question • What is solubility, and how is it determined? Unit IV • Investigation I-X
You will be able to: • Explain the concept of solubility and determine the solubility of a substance. Unit IV • Investigation I-X
Notes • Homogeneous: A mixture in which the substances are distributed uniformly. All solutions are homogeneous by definition. • Heterogeneous: A mixture that is not uniform throughout. Unit IV • Investigation I-X
Activity • Purpose: In this activity you will examine the solubility of five solutes in water. (cont.) Unit IV • Investigation I-X
Dye molecules View 1: Uniform distribution of molecules View 2: More molecules at the bottom (cont.) Unit IV • Investigation I-X
Making Sense • Explain how you can tell when a substance is soluble or insoluble in water. Unit IV • Investigation I-X
Notes • A solute is a gas, liquid, or solid that dissolves when mixed with another substance. • A solvent is the substance present in the greatest quantity in a solution. Solvents are usually liquids. (cont.) Unit IV • Investigation I-X
(cont.) • Soluble substances are solutes that dissolve completely. • Insoluble substances are those that do not dissolve at all. • Partially soluble substances are those for which only a certain amount will dissolve. Many substances are partially soluble. Unit IV • Investigation I-X
Check-In • There is solid sugar at the bottom of your tea. Why do the last sips taste sweeter? • All of the sugar in your tea is dissolved. The last sips taste the same as the first. Use a molecular view of sugar dissolved in water to explain why. Unit IV • Investigation I-X
Wrap-Up • Gases, liquids, and solids can dissolve in water. However, some substances are not soluble. • Partially soluble means that when two substances are mixed, a solution forms but one substance is leftover. • Solutions are homogeneous. The molecules or ions of the solute are distributed uniformly between the solvent molecules. Unit IV • Investigation I-X
Toxins Unit – Investigation I Lesson 4: Weighing In
ChemCatalyst • Which do you think is more toxic—one mole of arsenic, As, or ten grams of arsenic? Explain your reasoning. Unit IV • Investigation I-X
The Big Question • How is the mole concept used to connect the mass of a sample to the number of particles it contains? Unit IV • Investigation I-X
You will be able to: • Use the molar mass of a substance to find the number of molecules in a sample. Unit IV • Investigation I-X
Activity • Purpose: The purpose of today's lesson is to explore the relationship between mass and moles. (cont.) Unit IV • Investigation I-X
(cont.) (cont.) Unit IV • Investigation I-X
(cont.) Unit IV • Investigation I-X
Making Sense • How is measuring the mass of a substance the same as counting? Unit IV • Investigation I-X
Notes • The molar mass of a substance is how much one mole of that substance weighs. Molar mass is the sum of all of the atomic masses (in grams) in a chemical formula. (cont.) Unit IV • Investigation I-X
molar mass in grams/mole add the atomic weights of the atoms in the chemical formula moles 6.02 1023 (Avogadro’s number) of each of the atoms in the chemical formula mass in grams weight of the substance (cont.) Unit IV • Investigation I-X
Check-In • You have one mole of NaCl and one mole of KCl. Which one weighs more? Explain your thinking. Unit IV • Investigation I-X
Wrap-Up • The atomic weight on the periodic table is equivalent to the mass of 1 mole of atoms of the element in grams. • The molar mass of a compound is the sum of the atomic weights of the atoms in the compound. • Molar mass allows you to convert between moles and grams. Unit IV • Investigation I-X
Toxins Unit – Investigation I Lesson 5: Finding Solutions
ChemCatalyst • Consider the following solutions: • 1.0 L • 1.0 M C6H12O6 • (glucose) • 1.0 L • 1.0 M C12H22O11 • (sucrose) • 500 mL • 1.0 M C12H22O11 • (sucrose) (cont.) Unit IV • Investigation I-X