Looking up the Ph!

Josue TorresPeriod:3rdChemistry

Extra Credit lab5/28/2013

PurposeTo measure the pH of various household

materials by using a natural indicator to make an indicator chart.

Materials Knife Red cabbage leaves 1 cup measure Hot water 2 jars clean white cloth Teaspoon Tape 3 sheets of plain white paper Paper Marker 10 clear plastic cups White vinegar Backing soda Household ammonia Various household items Ruler

Procedure 1. Put ½ of finely cut cabbage leaves into one jar, then add ½ of hot

water. Stir and crush the leaves while stirring with a large spoon 2. Get a clean cloth and put it in a clean jar. ( that’s your natural

indicator)3. Tape 3 sheets of white paper from end to end, Draw a line down

the middle and number it from 1 to 14. this is your pH scale4. Pour about 1-cm of your indicator into three clear cups. Then to

one you add several drops household ammonia, then to the second one you add several drops of vinegar and then to the third one you add a pinch of backing soda. Then place them on the pH scale where they correspond.

5. Repeat step 4 for some household items, table salt, milk, lemon juice, laundry detergent, dish detergent, mouthwash, toothpaste, and shampoo.

Data Household Items

salt

Milk

Lemon juice

Laundry detergent

Dish detergent

mouthwash

toothpaste

Shampoo

Vinegar ammonia

Baking soda

Their pH 9 8 2 9-10 6-7 8-9 7-8 11 12 3-4 6

Conclusion/Analyze While I was doing this lab I was able to refresh my memory and good back onto

chapter 19. This lab was very useful because I was able to use it like a study guide for the final for Chapter 19 acids and bases. I also discover that when you put red cabbage in water the water turns purple. That was something new to me because I have never done this experiment. I also learn that if you put to much of the items the color might turn a non accurate color.

1. The color on the indicator for acidic was a dark red orange, then for neutral it was like a lime green with yellow in it, and for the basic it was like a blue violet.

2. I really think that one of the chemical change that occurred while doing this lab experiment was the transformation from on color to another.

3. While I was finding the pH for each household items all the items that were use for cleaning or for personal hygiene , they were mostly all basic expect ammonia. Mostly all of them landed around 7-9 on the pH scale.

STD: 5d. Students know how to use the pH scale to characterize acid and base solutions