Virtual Chemistry Lab

Sour Foods

Question(s):

What atoms are in sour foods?
What is it that makes some foods taste so sour?

Hypothesis:

Since pH [potenz power + H (hydrogen)] is the measurement of acidity and alkalinity, then the amount of hydrogen atoms present in a solution should be the deciding factor on its sourness.

Procedures:

The procedures are as followed:

1. Labeling a representative cup for each food bottle.
2. Add 5 drops to its corresponding numbered cup.
3. Add a drop of dye to each cup of food.
4. Using a pH (color) chart, arrange them from high concentration to low concentration of loose hydrogen atoms.
5. Identification of the type of food that was used for the experiment.

Data:

- Because of the color of the added dye, it represents the concentration of loose hydrogen atoms in the food.

- With the concluded arrangement of cups in accordance to their color scale, we are then able to determine the food with the highest and lowest concentration of loose hydrogen atoms; with the highest concentration being the sourest and the lowest concentration being the least sour.

Results:

- Q: What atoms are in sour foods? What is it that makes some foods taste so sour?

A: The reason why foods taste sour is because of the concentrated amount of hydrogen atoms.

- The following is a list of the food used in the experiment in descending order of the concentration of H atoms:

Labeled number:	Food:	Color:
3	Lemon Juice	Pink
4	Vinegar	Yellow
1	Orange Juice	Light green
2	Milk	Green
5	Water	Aqua

Therefore, the sourness of a food is dependent on the amount of hydrogen atoms present.

Holes in Bread

Question(s):

What molecules make the holes in bread?

Have you ever noticed the holes in bread?

Hypothesis:

The holes in bread may be produced by the chemical reaction from the mixing of yeast, sugar, and water producing a by-product of CO₂, which during the baking process gets pushed out of the bread itself through the application of heat which leaves a print of holes.

Procedures:

The procedures are as followed:

1. Add 3 scoops of yeast into a test tube.
2. Add 3 scoops of sugar into the same test tube.
3. Fill the test tube three fourths full with warm water.
4. Using a stick, stir together the ingredients until it is well mixed (water is the same color as the yeast).
5. Wait for a certain period of time to allow the reaction to take place.
6. Shine a flashlight outside the tube.
7. Observe the test tube carefully and look for tiny bubbles streaming up the side of the tube.

Data:

- Yeast, a living organism, feeds on the sugar molecule. It breaks down the sugar molecule apart to produce two new molecules: carbon dioxide gas molecules and alcohol molecules.

- The tiny bubbles that were previously observed in the test tube were the carbon dioxide molecules.

Results:

The chemical reaction taken place in the test tube is also what happens in bread, where yeast, added to the bread dough, breaks apart the sugar molecules in flour. Carbon dioxide molecules are made and trapped in the bread dough and leave holes when the bread is baked.

Sour Foods:

1. What are acids and bases?

Acids and bases (alkaline) is the measurement of a solution based on a pH scale with acidity measuring with a pH less than 7 and alkalinity measuring with a pH greater than 7; both on a given scale.

2. What is a molecule?

A molecule is a combination of two or more atoms.

3. Why is pH important in the ocean?

pH, being a part of the abiotic conditions that exists in the ocean, affects all the organism that live there. Slight increases in either acidity or alkalinity may seem to have little effects on the organisms; yet, on a larger scale, is a huge threat because of gas exchange. The pH may alter several living and reproductive conditions of organisms.

4. What is an ion?

An ion is an electrically charged particle that does not have a natural charge

Holes in Bread:

1. What gas causes the bubbles?

CO₂

2. How was the gas produced?

The gas was produced through a chemical reaction dealing with yeast, sugar, and water where the yeast, becoming active, broke down the sugar molecule to produce two by-products – CO₂ molecules and alcohol molecules.

3. How does CO₂ get in the ocean?

CO₂ gets in the ocean thru a process of gases moving back and forth from the atmosphere and water called gas exchange.