The Keyboard

The Keyboard

The keyboard is an electric substitute for the piano. When you strike a key on a real piano, it sends a small hammer forward, which strikes a string, making it vibrate. The string vibrating is what makes the sound of the piano key. When you strike a key on a keyboard, it sends an electric input to an arduino board, which then sends a signal to a speaker to create a sound. The white and black keys create two different sounds. The black keys are sharps/flats, and create much flatter notes in comparison to the white keys. Your right hand on the keyboard/piano plays a melody, while your left hand plays chords or a bassline.

Stevie Wonder

Stevie Wonder was born six weeks premature, causing a stunted growth in the back of his eyes, making his retinas detatch, causing him to go blind. 

Steve learnt to play piano at his local church.

Steve has 9 different children.

Stevie Wonder was in a car crash after a tour of his, leaving him in a coma for four days. When he woke up, he had a partial loss of his sense of smell.

The Biuret Test

Aim:
To test if a sample of food contains protein.

Equipment:
Test tube,
sodium hydroxide,
copper sulfate,
food sample.

Method:
1. Place about 2mL of the food sample into a test tube and add 5 drops of sodium hydroxide.
2. Add 5 drops of copper sulfate.
3. Gently shake test tube from side to side.

Results:
For our experiment, the liquid did not change colour. The copper sulfate, which is blue, is supposed to turn green upon being added to the liquid, and then purple once shaken.

This did not happen.

Our liquids, whether or not protein was present, stayed green/blue even when heated.

Discussion:
Protein is made out of amino acids.

The Biruet Test uses an alkaline mixture, composed of copper sulfate. This alkaline mixture turns purple in the presence of peptide bonds, which hold amino acids together.

Testing for Carbohydrates

Benedict's Test

Aim:
To test a sample of food to determine whether it contains simple sugars.

Equipment:
Bunsen burner,
test tube tongs,
Benedict's Solution,
a sample of food.

Method:
1. Place about 2mL of the sample into a test tube and then add 5 drops of Benedict's solution.
2. Heat with a Bunsen burner until it changes colour. Do not boil.

Results:
A positive test for a simple sugar results in Benedict's Solution changing from a blue colour to an orange colour.

Discussion:
Benedict's Solution is used to test for simple carbohydrates. Benedict's test identifies the monosaccharide's and disaccharides (reducing sugars), which have aldehyde functional groups or free ketone.

Conclusion:
Benedict's Test is used to test for simple sugars (simple carbohydrates). If there are simple carbohydrates present in a food sample, Benedict's solution will change colour, from blue, to orange.

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Iodine Test

Aim:

To test if a sample of food contains complex sugars.

Equipment:

Test tube,

food sample,

iodine solution.

Method:

1. Place about 2mL of the sample in a test tube.

2. Add 3-5 drops of iodine and mix.

Results:

If complex sugars are present, the iodine solution will change from a brown colour to a blue/black colour.

Discussion:

Iodine is used to test for the presence of starch, which is a complex sugar (complex carbohydrate). Starch turns into a very dar black colour once iodine is added, because of an intermolecular charge-transfer complex. If starch isn't present, a brown colour will remain.

Conclusion:

Iodine will turn black in the presence of starch.