Preparing Testing Solutions

Procedure

1. Fill the jar with distilled water.
2. Add the brom thymol blue to the jar.
3. Secure the lid and shake the jar to mix. Note: If the solution appears green or yellow, add one drop of household ammonia (one drop at a time) until the indicator appears blue.

Calcium Hydroxide (Limewater)

Materials

2 1-quart (l-liter) glass jars with lids

distilled water

calcium oxide (lime used to make pickles)

masking tape

marking pen

Procedure

1. Fill one jar with distilled water.
2. Add 1 teaspoon (5 ml) of calcium oxide and stir.
3. Secure the lid and allow the solution to stand overnight.
4. Decant (pour off) the clear liquid into the second jar. Be careful not to pour any of the lime that has settled on the bottom of the jar.
5. Secure the lid and keep the jar closed.
6. Use masking tape and a marking pen to label the jar "Limewater."

Monosaccharide Testing Solution

Materials

copper scrubbing pad

1/2-pint (250-ml) jar with lid

household ammonia

piece of cardboard large

enough to cover top of jar

Procedure

1. Put the scrubbing pad into the jar.
2. Fill the jar with the ammonia. piece of cardboard large enough to cover top of jar
3. Cover the top of the jar with the cardboard to reduce the escaping ammonia smell.
4. Place the covered jar where it can remain undisturbed for 24 hours.
5. Remove the scrubbing pad.
6. Secure the lid on the jar and store in a cool area.

Phenolphthalein

Materials

4 tablespoons (60 ml) of rubbing alcohol

2 baby-food jars (one with a lid)

1 Ex-Lax® tablet

spoon

Procedure

1. Pour the rubbing alcohol into the first jar.
2. Break the Ex-Lax tablet into small pieces and place them in the jar of alcohol.
3. Use the spoon to crush and stir the tablet pieces. Note: The tablet will not dissolve completely. Pieces will settle to the bottom of the solution.
4. Decant the clearer liquid at the top into a clean jar.
5. Secure the lid on the jar to store.

Red Cabbage Exract

Materials

small head of red cabbage

2-quart (2-liter) cooking pot

distilled water

tea strainer

1-quart (1-liter) jar with lid

Procedure

CAUTION: Take care when heating the liquid and do not remove the pot from the stove until it cools to room temperature.

1. Tear or cut the cabbage leaves into small pieces and place them in the cooking pot
2. Fill the pot with distilled water.
3. Boil for five minutes. Allow to cool to room temperature.
4. Pour the cooled cabbage extract through the tea strainer into the jar. Discard the cabbage leaves.
5. Store the concentrated cabbage extract in a refrigerator until needed.
6. When ready to use, mix equal parts of the concentrated cabbage extract and distilled water.

Sodium Chloride Solution (0.9%)

Materials

9 grams of sodium chloride (table salt)

991 ml of distilled water

1-quart (1-liter) jar

Procedure

1. Combine the sodium chloride and water in the jar.
2. Stir until the sodium chloride dissolves.

Note: The following procedure is a little less accurate, but it is fine for most experiments in this book.

1. Combine 1 teaspoon of sodium chloride with 1 quart (1 liter) of distilled water.
2. Stir until the sodium chloride dissolves.

Starch Solution (1%)

Materials

1/2 teaspoon (2.5 ml) of cornstarch

1 cup (250 ml) of distilled water

small saucepan

I-pint (500-ml) jar with lid

Procedure

1. Mix the starch with 1 tablespoon (15 ml) of the water to form a paste.
2. Boil the remaining water in the saucepan and slowly add the starch paste.
3. Cook for two minutes, stirring constantly. Allow to cool.
4. Pour into the jar and secure the lid.