12/15 - 8th Grade Agenda Learning Objective: Learn about Acids & Bases Collect HW: Reading & Notetaking: p.126 – 128 Textbook Reading p. 262 - 270 HW: Reading & Notetaking p.129 – 131 Reminder HW: Science Fair Background due 1/13 & 1/14 (10 Points)

Daily Reflection Prompt: Write 3 questions that you have about Acids and Bases.

How can you test this is sugar water or salt water without drinking it? You can test the electrical conductivity of the solution. If no ions are present (as in a sugar solution), current wil not flow.

Why do they use salt to melt ice on the road? Freezing point of water will be lowered. It’s also how they make ice cream In general Solutes lower the freezing point of solvent

What happens to the boiling point of water when you add salt to it? boiling point of water will be raised. That’s why cooks add salt to boiling water before adding the spaghetti In general solutes raises the boiling point of solvent

Why does solutes lower freezing and raise boiling point? Solute particles interfere with the change of state

What is Solubility? Solubility is a measure of how much solute can dissolve in a solvent at a given temperature

What is unsaturated solution? If you can continue to dissolve more solute, it is a unsaturated solution

What is unsaturated solution? When you’ve added so much solute that no more dissolves, you have a saturated solution.

What are the factors that affect the solubility of a substance? Pressure Temperature Type of Solvent

Higher Pressure can increase the solubility of gases Opening a can of soda reduces pressure and carbon dioxide escapes. Scuba divers need to come up from a deep dive slowly or nitrogen bubble form in the blood stream (The Bends)

Some solvents and solutes are not compatible Oil and Vinegar won’t mix Latex Paint can be cleaned up with soap and water Oil based paint require nonpolar solvent such as turpentine.

Solubility of Solids increases as the temperature increases This is why you can add more solute when you heat up the solvent. Solubility of gas decreases as the liquid temperature goes up (This is why a warm soda is flat).

pH pH: means potential of hydrogen (Positive Ion) Scale goes from 0 to 14 0: Very acidic (hydrochloric acid) 7: Neutral (Water) 14: Very basic or alkaline (Drain Cleaner)

What are properties of an acid? It tastes sour It reacts with metals and carbonates It turns blue litmus red.

What are some common use of acids ?

What are properties of a bases? It tastes bitter Slippery feel Reacts with acids Turns red litmus blue

What are some common use of bases ?