We use cookies to give you the best experience possible. By continuing we’ll assume you’re on board with our cookie policy

Demonstrating the Importance of Surfactant Essay Sample

The whole doc is available only for registered users OPEN DOC

Get Full Essay

Get access to this section to get all help you need with your essay and educational issues.

Get Access

Demonstrating the Importance of Surfactant Essay Sample

Surfactant is an essential component for the respiratory system to function properly. This experiment was administrated to help us understand better the role of surfactant in the alveolar system. Surfactant is a detergent-like substance produced by the Type II alveolar cells in the alveoli. Surfactant is produced to make it easier for people to breath by reducing the surface tension of the water molecules that primarily compose the walls of the alveoli; it helps them to not stick together. For this experiment, we will be using milk and food coloring to represent the water (milk) and gas (food coloring) in the respiratory system. Because I know milk is non-polar and food coloring is polar, my hypothesis predicts the two will not mix voluntarily at first, but the soap acting as a surfactant, when added, will help the two liquids mix together.

(Part on: water surface tension)
1- A penny
2- A dropper
3- Water
4- Paper towels

(Part two: surfactant)
1- Milk
2- 2 different color food coloring
3- Dishwashing soap
4- Cotton swab
5- A mall clear dish
6- Timer
7- Paper towel
8- Water

(Part one: water surface tension)
1- Place the penny in a flat area
2- Fill a dropper with water
3- One by one add the drops of water to the top of the penny
4- Measure how many drops fit until the drops break the surface tension of the water.
5- Record results the results table  (Part two: surfactant)
6- Placed the dish in a flat steady surface.
7- Then poured the milk making sure the whole bottom of the dish is covered.
8- Add four drops of food coloring to the center of the dish.
9- Let it rest for two minutes and then measure how far the coloring expanded.
10- Record in the result chart
11- Dip the cotton swab in soap
12- Place the end of the cotton swab in the middle of the dish containing the milk and the food coloring.
13- Observe what happens to the food coloring and record the result in the results chart.
14- Throw away the liquids and leave station clean after recording results.

(Part one: water surface tension)
The average drops of water that a penny can hold without spilling the water is 24 drops. In my experiment the results were the following: Trial number
Number of drops
Try one
Try two
Try three

(Part two: surfactant)
When the coloring was placed in the milk at the beginning, it didn’t expand through the milk as quickly as when the soap was added. Without the soap
Expanded 5 ml/min from the center.
With the soap
Expanded at 5cm/ sec from the center.

My hypothesis is accepted. After I applied the drop of soap to the milk, the food coloring spread around. Why? At first, the food coloring just sat on the surface of the milk. That’s because food coloring is less dense than milk, so it floats on the surface. The milk didn’t mix with the food coloring in the beginning because it wasn’t stirred together. The soap reduces the surface tension of the milk by dissolving the fat molecules, which is why whole milk works better. The surface of the milk outside the soap drop has a higher surface tension, so it pulls the surface away from that spot. The food coloring moves with the surface, streaming away from the soap drop. Due to the convection that results from the moving surface, the food coloring may be drawn down into the liquid, only to appear rising again somewhere else. When the soap finally gets evenly mixed into the milk, the action stops. If another drop of soap is added, the process starts all over again. This won’t work in water because water doesn’t contain any fat.

We can write a custom essay

According to Your Specific Requirements

Order an essay

You May Also Find These Documents Helpful

Designing an Osmotic Potential Experiment with Potatoes

Osmosis is used throughout the kitchen in various countries. In France, aubergines and cucumbers are often soaked in salt to create a nicer texture, however chefs lack understanding of why this happens, as they would have forgotten about it after they finished school, they only know that it happens. Therefore, this experiment is designed to explain to the millions of chefs around the world why...

Investigating the Effects of Salt on Seed...

PROBLEM/RESEARCH QUESTION In this investigation, we are researching and investigating whether the concentration/percentage of NaCl (salt) in water affects the germination rate of seeds and if so, which concentration germinates the most seeds. We will formulate our research by conducting an experiment in which we will observe the germination of seeds in various concentrations of salt water and evaluate the results gathered. In particular, we...

Investigating the Effect of Sodium Fluoride on...

Graph Showing the effect different volumes of Sodium Fluoride has on the average rate of production of H+ ions as measured by the colour change of resazurine Comment on Graph: The graph depicts a positive trend, as the amount of Sodium Fluoride increases the average rate of H+ ions as measured by the colour change of resazurine also increases. This increase is consistent with each...

Effect of Salinity on Germination

Colour used to indicate the raw data used to calculate example mean Colour used to indicate the raw data used to calculate example standard deviation Raw Data table 2 showing the effect changing the salinity of water added to ten ungerminated Vigna radiate (mung bean) seeds has on the seeds ability to successfully germinate as determined by the visible presence of a radicle seven days...

To Investigate the Effect of Regular Mowing...

T Test A T Test has been conducted to determine whether there is a marked difference in the heights of white clover petioles in mown and unmown areas, Null hypothesis: there is no significant statistical difference between the heights of petioles of white clover in unmown and mown areas. Alternative hypothesis: there is a significant statistical difference between the heights of petioles of white clover...

Get Access To The Full Essay
Materials Daily
100,000+ Subjects
2000+ Topics
Free Plagiarism
All Materials
are Cataloged Well

Sorry, but copying text is forbidden on this website. If you need this or any other sample, we can send it to you via email.

By clicking "SEND", you agree to our terms of service and privacy policy. We'll occasionally send you account related and promo emails.
Sorry, but only registered users have full access

How about getting this access

Become a member

Your Answer Is Very Helpful For Us
Thank You A Lot!


Emma Taylor


Hi there!
Would you like to get such a paper?
How about getting a customized one?

Couldn't Find What You Looking For?

Get access to our huge knowledge base which is continuously updated

Next Update Will Be About:
14 : 59 : 59
Become a Member