Name: Date:

Practice with Carbohydrate Dehydration Synthesis and Hydrolysis

Background:

In a chemical reaction, energy and matter is neither created nor destroyed. The atoms themselves merely rearrange themselves to create new compounds.

There are two forms of chemical reactions; dehydration synthesis and hydrolysis. Dehydration Synthesis is the process in which two monomers join together. In this reaction, water is created as a bi-product. Hydrolysis is the process in which a polymer is split into monomers. Water is put into the reaction for this separation to take place.

You will get practice in demonstrating how dehydration synthesis and hydrolysis take place. Follow the instructions below.

Materials:

Dehydration Molecules Page

Hydrolysis Molecules Page

Scissors

Tape

Part 1: Representing Dehydration Synthesis

1.  Cut out 2 monomers, 1 arrow, and a water droplet.

2.  Place an arrow on the table.

3.  Place monomers next to each other to the left of the arrow. Are the molecules on the left side of the equation reactants or products?

______

4.  Cut out an OH of one monomer and H on the other monomer (cut along the squares). Place the H and OH together on the droplet. Tape together the two monomers (Hint: the two monomers bond where there is an O single covalently bonded off of the ring)

What do the H and OH bonded together in the droplet represent?______

What do the two monomers taped together represent? ______

5. Place the taped monomers and droplet on the right side of the arrow.

Are the molecules on the right side of the equation reactants or products?______

6.  Describe each step of dehydration synthesis (include reactants, the chemical reaction, products, role of water in dehydration synthesis).

Part 2: Hydrolysis

1.  Cut out a polymer, water molecule, and arrow.

2.  Place an arrow on the table.

3.  Place a polymer and water next to each other to the left of the arrow on the table. The polymer and water are on the left side of the chemical reaction. Is a molecule on the left side of the equation a reactant or product?______

4.  Cut an H off of the water molecule (cut along box) to create an H and an OH.

5.  Locate the O bond connecting the two monomers. Cut along the dotted line next to the O to create 2 monomers.

6.  Attach the H and OH so that you have 2 hydroxyl (OH) groups on both monomers. This is the product of the reaction. Which side of the arrow should your two resulting monomers go on? ______

7.  Describe each step of hydrolysis (include reactants, the chemical reaction, products, role of water in hydrolysis)