Experimental Methods For Measure The Contact Angle Of Particles At Fluid Interfaces

Depending on the polarity of the components of the mixture, different compounds will travel different distances up the plate. More polar compounds will "stick" to the

The aim of this experiment was to measure the angle between a metal surface and a liquid droplet using a CCD camera and optics. This experiment also investigated how metal surfaces coated with single-molecule layers of functionalized alkanethiols and alkanethiols alter the wetting behavior and metal surface energy.

The purpose of this experiment was to see if a penny could hold more drops of salt water or tap water. It was found that a penny could hold an average of 22.3 drops of tap water and only 20.8 drops of salt water. These results are consistent with the hypothesis: If the salt concentration of water impacts the amount of water a penny holds, then the penny will hold less drops with salt water. While dropping the water onto the penny, it was observed that the water formed into a dome-like shape on the penny. It looked like the individual drops of water turned into one large drop of water. This was observed for both the tap and salt water. This happened due to the cohesion and surface tension of water. Cohesion simply means that water molecules are attracted to each other and want to cling together. Surface tension is the special term that is applied to the cohesion of water molecules.

Of the two alkane liquids studied n-Hexane was determined to have the stronger IMF of attraction by virtue of its experimentally determined lower ?T. Conversely n-Pentane has weaker IMF of attraction due to its larger ?T. As explained at length above, this is because it takes more energy to excite a molecule in liquid to leave (vaporize or become gaseous), when there are stronger IMF of attraction holding the molecules together in liquid form.

Introduction: The purpose of this lab is to see how fast an Alka-Seltzer tablet dissolves in water when the surface area increases. Problem Statement: How does surface area influence the Alka-Seltzer tablet on how fast it can dissolve in water? Hypothesis: If the surface area increases then the time it takes to dissolve will decrease. Investigation Diagram (ID)

The results of the experiment were that salt water had the most surface tension with an average of 42.4 drops. The liquid with the next highest surface tension was plain water with an average of 35.7 drops. Finally, the water with detergent had the least surface tension with an average of 23.9 drops. Adding salt to the water strengthened the hydrogen bonds, causing it to have more surface tension. Adding detergent to the water weakened the surface tension, causing less drops to stay on the

When an object falls onto the surface, it has to push the water molecules apart. If the effect of the weight of the object is insufficient to match the attractive forces between molecules in the surface layer, the object will not enter the surface.

6. The solubility of the solids were tested using a micro tray, by placing them in water and oil to observe their polarity,

A rougher candy surface such as, Mentos, means there are more places for bubbles to grow, or more nucleation sites. (brilliant.org) Surfactants are compounds that lower the surface tension between two liquids. (brilliant.org) Dropping Mentos in Coke is an example of a surfactant. The eruptions happen due to nucleation where the Carbon Dioxide in the soda is drawn to the Mentos. (eepybird.com) The pressure of the bottle is trapping the CO2 inside. The CO2 in the soda reacts to the sugar on the Mentos.

Note 1: These are intermolecular forces of attraction so they occur OUTSIDE of the molecules!

Surfactants, when dropped in water, will try to spread across the surface of the water. While spreading along, it is also pushing away from the surface of the water. So when an object is placed onto the water, the surfactant is pushing the object away from the water, (while spreading), causing it to

see more why the results were what they were. The study was done in New Zealand, what is the

Non-Newtonian fluids. What do they do? What are they? A Non-Newtonian fluid is a fluid or liquid that can turn to a solid when pressure is applied. In specifics with oobleck (which is what I used) (made with cornstarch & water) the cornstarch particles get scrunched together like snow in front of a snowplow. So what happens if you hit it? Or run on it? Or poke it? I think it will turn solid right?

aid the initial water uptake and growth even of particles dominated by very low-solubility compounds (Andreae 2008)

Weight data and images showing the physical appearance of the BPs are shown in Figure 3 and 4, respectively. Acetone-cleaned AD BPs lost approximately 26, 48, and 32 % of their weight, whereas methanol-cleaned AD BPs decreased their weight by around 29, 40, and 34 % at 300 ˚C for 90 min, 350 ˚C for 60 min, and 300 ˚C for 120 min, respectively. HiPco BPs lost about 22, 5, and 1 % at 350 ˚C for 30 min, 300 ˚C for 30 min, and 250 ˚C for 30 min, respectively. However, when we recalculated the weight change from the theoretical weight of AD BPs considering the surfactant effect, + 5, - 25, and - 2 % weight of acetone-cleaned AD BP were changed after HT at the first (300 ˚C - 90 min), second (350 ˚C - 60 min), and third (300 ˚C - 120 min) conditions while there were + 5, - 13, and 0 % changes in weight for methanol-cleaned AD BPs. As a result, at the first and third conditions, the weight change of AD BPs weight change was minimal and while for HiPco BPs weight change was minimal at the second and the third conditions.