Stull_Lab#7

Lab Assignment #7 Write-Up: Acid-Base Chemistry Chapter 1 Lab Write up: 30 points Photos: 5 points (upload photos to the end of your lab write-up) Total: 35 points Purpose: (1 point) Of Exp. # 7: As it relates to CHE 101: Experimental Data: Data Table 1: Data Collected from Exercise 1. (8 points) ID Number Chemical Name Chemical Formula Hypothesis: Acid or Base pH BTB Color Acid or Base? 11A Acetic acid CH 3 COOH 11B Hydrogen nitrate HNO 3 11C Hydrogen sulfate H 2 SO 4 11D Phosphoric acid H 3 PO 4 11E Sodium acetate CH 3 COONa 1 Nam e

11F Sodium bicarbonate NaHCO 3 11G Sodium dihydrogen phosphate NaH 2 PO 4 11H Sodium hydrogen sulfate NaHSO 4 12A Sodium bisulfate NaHSO 3 12B Limewater Ca(OH) 2 12C Trisodium phosphate Na 3 PO 4 12D Disodium hydrogen orthophosphate Na 2 HPO 4 12E Ammonium hydroxide NH 4 OH 12F Hydrochloric acid HCl 12G Sodium carbonate Na 2 CO 3 12H Sodium hydroxide NaOH Questions: A. What is the value of using pH paper as an indicator? (1 point) B. What is the value of using BTB as an indicator? When might BTB be a better choice than pH paper? (1 point) C. Write the chemical equation of mixing Acetic acid (CH 3 COOH) with water. (1.5 points) 2

B. What factors determine if neutralization occurs during an acid-base reaction? (1 point) C. In all the chemical reaction performed in Exercise 2, neutralization occurs when the pH is neutral (7) or basic (>7). Did any of the reaction not result in a color change of the BTB indicator from yellow (acid) to blue (base)? Explain why neutralization may not have occurred in one or more reactions. (1 points) D. Write chemical equation for neutralization of sulfuric acid with KOH. (1 points) Data Table 3. Household Acids and Bases. (3 points) Possible substances to test include home cleaning products, glass cleaner, liquid detergent, bleach, soft drinks (it is better to use clear or light colored drinks such as 7 Up, sprite,…), liquid from food items, etc. Household substance Prediction: (Acid, Base, or Neutral) pH Valu e Conclusion: (Acid, Base, or Neutral) Prediction Correct? (Yes or No) 4

Question: A. What properties did you use to determine whether the substances you tested were acid or base? (1 point) 5