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Exploration of slime – functional groups and property changes in carbon based molecule

1 – What functional groups can you see in these molecules? How might this be similar to the structure of water?


2- Given the structure of the two molecules what type of bonds do you think would be formed between them and why?



3 – Which slime mixture is the most bouncy, thicker? Why?

4 – Consider the molecular structure (functional groups and bonds). Why do think the glue (the main structural component) changed as you described in 3? Basically, why does slime form in this mixture?


5 – The molecule below is called acetic acid (the acid you taste in vinegar). Draw how this molecule dissociates in water to make a solution more acidic.


6 – If you add acetic acid to the slime do you think it would get thicker or more liquid? Provide a chemical reaction based explanation for why you think the changes would occur.

User Littlely
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Exploring the functional groups, bonds, and reactions within slime ingredients helps us understand its properties and behavior. Understanding the interplay between PVA, borax, water, and other additives allows us to customize slimes for different textures and consistencies. Remember, experimentation is key to unlocking the fascinating world of slime!

1. Functional Groups and Water Similarity:

Unfortunately, the molecules you mentioned are not provided. However, typical slime ingredients like polyvinyl alcohol (PVA) and borax contain various functional groups:

PVA: hydroxyl (-OH) groups allow hydrogen bonding with water molecules.

Borax: borate (-BO32-) ions interact with hydroxyl groups on PVA, cross-linking them into a network.

This ability to hydrogen bond with water is similar to water itself, enabling slime to absorb water and become thick.

2. Bond Types and Formation:

Between the PVA and borax molecules, the following bonds form:

Hydrogen bonds: Hydroxyl groups on PVA and oxygen atoms in the borate ion attract and form hydrogen bonds, holding the slime together.

Ionic bonds: Sodium ions in borax interact electrostatically with the negatively charged borate ion, stabilizing the borate structure.

These bonds contribute to slime's unique properties like elasticity and viscosity.

3. Slime Mixture Properties:

The optimal slime mixture depends on the specific ingredients and their ratios. For example:

More borax: Creates a thicker, bouncier slime due to increased cross-linking between PVA chains.

More PVA: Can make the slime too stiff and less bouncy, requiring additional water for balance.

4. Glue Change and Slime Formation:

The "glue" in slime refers to the cross-linking network formed by PVA and borax. Changes in slime consistency arise from:

Borax concentration: Higher concentration increases cross-linking, leading to a thicker slime.

PVA/borax ratio: Excess PVA can disrupt cross-linking, making the slime runny.

Water content: More water increases the volume and reduces the slime's viscosity, making it thinner.

5. Acetic Acid Dissociation in Water:

Acetic acid in water dissociates as follows:

CH3COOH + H2O --> CH3COO- + H3O+

The hydrogen ion (H3O+) contributes to the acidic nature of the solution.

6. Slime and Acetic Acid:

Adding acetic acid to slime can have two effects:

Thickening: Low pH can strengthen hydrogen bonding between PVA and water, making the slime thicker.

Liquefaction: High acetic acid concentration can disrupt borate-PVA interactions, weakening the cross-linking network and making the slime thinner.

The overall effect depends on the specific concentration and type of slime ingredients.

User Ryan French
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