IPS 4.9 Quiz Study Guide

Due March 16, 2015

Part I

Phenol Red

PH indicator


  • Red: Basic
  • Clear: Acidic

Observations on Phenol Red Experiments

Phenol Red in water- pink

With carbon dioxide over water- orange

With carbon dioxide in water- yellow

Notes on Phenol Red Experiments

  • Phenol red changes color as you add carbon dioxide to water
  • The carbon dioxide turns to carbonic acid lowering the PH of the water
  • Calcium is more soluble in cup with straw
  • The carbonic acid lowers PH and dissolves calcium faster
Big image

Examples of Substances on PH scale

Part II

Observations on Alka-Seltzer Experiments

Substance 1 (no straw)- a little of it dissolved

Substance 2 (with straw)- Most of it dissolved

Experimental Errors

  • Not enough phenol red
  • Do not bubble water long enough
  • 2 cups do not have same amount of water

Ocean Acidification

Ocean's PH has decreased 0.1

  • About 25% drop in PH --> normal ocean PH: 8-8.4
  • Lower PH will cause shelled animals (shrimp, mollusks etc...) to not be able to build a shell