1. SNC 2D1

2. You will be presented with 6 clear, colourless, labelled solutions in test tubes: Sol’n 1 – HCl, diluted Sol’n 2 – NaOH, diluted Sol’n 3 – tap water, H 2 O Sol’n 4 – distilled water, H 2 O Sol’n 5 – Kosher salt (NaCl) + water Sol’n 6 – dextrose (table sugar - C 6 H 12 O 6 ) + water PROBLEM

3. A. Classify each as ionic or molecular, with 2 points of evidence for each. B. Classify each as either an acid or a base, with 2 points of evidence for each. C. Discuss: are acids and bases ionic or molecular? Why? D. Disucss: How does your lab evidence support Arrhenius’ definition of acids & bases?

4. 1)Research/Observation 2)Question 3)Theory 4)Hypothesis 5)Test INQUIRY PROCESS

5. MONDAY & WEDNESDAY, OCT. 21 & 23, 2013 Make use of the computer lab to research your problem & materials. FRIDAY OCT. 25, 2013 Lab day! Use any of the materials listed below to address the Problem. Submit lab report at the end of class. EXPECTATIONS 6 prepared and fully labelled solutions Conductivity testers Stir sticks, scoopulas Beakers, graduated cylinders Test tubes, test tube racks Spot plates, eye droppers Red + blue litmus paper Methyl red indicator Methyl orange indicator Bromthymol blue indicator Phenolphthalein indicator Hot plates, thermometers

6. REPORT Include the following headings: Research/Observation Question (How?, Why?) Theory/Model (suggest an answer or procedure) Hypothesis (formal & detailed) or Prediction (informal: “I think…”) Test showing Evidence (‘results’ can include tables, notes, diagrams, etc.) Analysis (include calculations, graphs, etc. here) Conclusions and Inferences (refer to results/analysis, answer questions, pose new questions, critique your inquiry process, suggest further investigations) * Remember to cite your sources

7. GUIDING YOUR RESEARCH I (STRONGLY!) suggest that you copy and paste the following tables into word, and fill them in for Friday’s lab. 1) Indicators reference table Acid (pH:_____) Base (pH:____) Water (pH:__) Red litmus paper turns red etc… Blue litmus paper Methyl orange etc… Spot plate

8. GUIDING YOUR RESEARCH 2) Ionic vs. Molecular (covalent) summary table Ionic compoundMolecular (covalent) compound Formula looks like? Melting point Boiling point Structural strength Conductivity Solubility (etc…)

9. GUIDING YOUR RESEARCH 3) Properties of acids vs. bases table ACIDSBASES Taste, feel, … Chemical formula looks like? When added to water, it… Changes RED litmus paper to… Changes BLUE litmus paper to… pH range (etc…)

10. GUIDING YOUR RESEARCH 4) Arrhenius’ definition of acids and bases: ACIDS break down in water, increasing the concentration or presence of ____ ( H + or OH - ?) ions in that solution BASES break down in water, forming higher concentrations of ____ ( H + or OH - ?) ions in that solution Svante Arrhenius was awarded the Nobel Prize in Chemistry, 1903, for his hydrogen theory of acids!!

11. GUIDING YOUR RESEARCH 5) pH scale – what does it mean? Grapes are 3 ‘jumps’ left of milk, so they are 10x10x10 = 1000 times more acidic than milk. They produce 1000 times more H + ions than milk Bleach is 4 ‘jumps’ right of eggs, so it is 10x10x10x10 = 10 000 times more basic or ‘alkaline’ than eggs. They produce 10 000 times more OH - ions than eggs

12. strrong acid weak acid weak alkali strong alkali NEUTRAL Bases (alkalines) produce more OH - ions in water Acids produce more H + ions in water Neutral solutions have equal numbers of OH - and H + ions