What is the difference between a solution and a suspension? Tuesday Nov 18th-Week 15 TOPIC: Acid/Base/pH  OBJ : 9-11 DO NOW: EXT: 6.4 Vocab DUE DATE: Friday DW: Acid & Base WKSHT ----------------------------------------------------------------------------------------------------------------- EXIT: Fill in your level of understanding RELATE the importance of buffers to live cells. Science of Life What is the difference between a solution and a suspension? HANDOUTS to PICK-UP: -6.3 Notes -Acid/Base Worksheet -6.4 Vocab SEMINAR 2: -Quiz for 6.1 & 6.2 BEFORE/AFTER SCHOOL: DW-Solute/Solvent -Finish 6.3 Notes -Video -Acid Base WKSHT -6.4 Vocab (Due Friday) ABSENT AGENDA

Tuesday   Tuesday: ___11__/__18___ OBJECTIVE…#_9-11_____ TOPIC: Acid/Base/pH Daily Work Grade- Solute/Solvent WKSHT DW GRADE: 2 1 0 DO NOW Q: what is the difference between a solution and a suspension? A: A solution is a homogenous m mixture, and a suspension is a heterogeneous mixture.

Today’s Objectives 9--- IDENTIFY how the properties of water make it well suited to help maintain homeostasis in an organism   10---DETERMINE pH of various substances and DESCRIBE the use of the pH scale 11---COMPARE / CONTRAST acids and bases and DESCRIBE how buffers affect cells.

These should be done by test day! Vocabulary -polar molecule / nonpolar molecule -hydrogen bond -acid / base -pH / buffer -adhesion / cohesionH These should be done by test day!

ACIDS/BASES/pH ACIDS -increase in hydrogen ions -a solution that has an excess of H+ ions HYDROGEN IONS- -positively charged ion of hydrogen H+ BASES -decrease in hydrogen ions -a solutions that has an excess of OH- ions HYDROXYL IONS- -negatively charged ion of hydroxide OH-

Acids & Bases Examples

ACIDS/BASES/pH release MANY H+ release FEW OH- WATER release FEW H+ release MANY OH- Say What? When you put molecules into water they can break down and release Hydrogen Ions and Hydroxide Ions

ACIDS/BASES/pH pH- “power of the hydrogen ion” -ion: charged atom or molecule IDENTIFY what the pH scale measures- -how acidic / basic substance is -substances INCREASE / DECREASE # H+ ACIDIC NEUTRAL BASIC   7 14

pH Play this game!

-bring organism back to balanceHOMEOSTASIS BUFFERS -solution which RESIST changes in pH when small quantities of an acid or alkali added to it. -keep pH "in range": 6.5 - 7.5 -Organisms SURVIVE and FUNCTION despite metabolic activities that shift pH (acid/basic end of scale) DISCUSS/IDENTIFY the importance of buffers in biology. -bring organism back to balanceHOMEOSTASIS et's consider the action of a buffer composed of the weak base ammonia, NH3, and its conjugate acid, NH4 +. When HCl is added to that buffer, the NH3 "soaks up" the acid's proton to become NH4 +. Because that proton is locked up in the ammonium ion, it proton does not serve to significantly increase the pH of the solution. When NaOH is added to the same buffer, the ammonium ion donates a proton to the base to become ammonia and water. Here the buffer also serves to neutralize the base.

Putting it all Together

Vocabulary 6.4 Vocab Name:__________________HR:_______ Front: 2 Coloumns/ 3 rows Back: 1 Column of 3

DATA ANALYSIS 1- IDENTIFY the independent variable. -pH/temp 2- IDENTIFY the dependent variable. -protease activity 3- IDENTIFY the range of pH values used in the experiment. -pH range 5-12 4- IDENTIFY the range of temperatures used in the experiment. -temp range 30-90C

DATA ANALYSIS 5- SUMMARIZE the results of the two graphs. -highest activity pH10 / 60C 6- INFER/SUPPORT- if laundry detergent is basic and requires hot water to be most effective, would this protease be useful? Yes, because the enzyme had the highest activity at a high pH (basic) and at a high temp.

EXIT FILL-IN: level of understanding of today’s objective    EXIT: