Warm-Ups: October 1-5, 2012 How to Write a Conclusion

Monday, October 1, 2012 Answer the Question: How is pH useful in determining water quality? The level of pH has a major affect on the water quality of a river. If the water has a pH level below 6.5, the water is acidic just like lemon juice with a pH of 2. If the water has a pH level above 7.5, the water is considered basic, just like baking soda with a pH of 8. At both the above pH levels the water quality is considered unhealthy and insects such as the caddis fly, stonefly and mayfly will not survive.

Wednesday, October 3, 2012 Respond to the hypothesis: If multiple liquids are tested for pH, then the liquid can be determined to be an acid, base or neutral because the cabbage juice color can be compared to the indicator chart. The hypothesis is accepted because different liquids were determined to be an acid, base, or neutral based upon what color the cabbage juice changed to and then comparing the new color to the indicator chart. For example, apple juice turned to a dark red color which means it as a pH of 3-4 and is acidic. Also baking soda turned blue which means a pH of 8 and makes baking soda a weak base.

Thursday, October 4, 2012 The data was not reliable because: (address the procedures of the lab) The color of the liquids was left to human judgment and one person may think that vinegar turned violet which would be a pH of 5-7. Another person may have thought the color was red and meaning vinegar had a pH or 3-4. Another reason the data is not reliable is the liquid was not measured accurately. Thus the amount of liquid compared to cabbage juice did not stay consistent throughout the lab.

Friday, October 5, 2012 Other questions that still need to be answered (must relate to further investigation of the same data): Is there another way to check for pH levels that is more accurate? In the future, this lab would include a wider variety of liquids, since only one base was tested.

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