Quiz with the Answers.

Who directed the movies "Jaws", "Schindler's List" and "Jurassic Park"?


Steven Spielberg

What is the largest country, by area, in the European Union?

France

Aboard which US warship did the Japanese sign their surrender in World War II?


USS Missouri

What is the minimum number of points required to win a tennis tie-break?


7(Seven)

How many stars are on the flag of the European Union?

12 (Twelve)

Which two countries have only won the football World Cup only once?

England and France


What was the name of the theatre where US president Abraham Lincoln was assassinated?

Fords

What do the initials FBI stand for?

Federal Bureau of Investigation

How Soap Cleans



Soap is an Emulsifier


A soap micelle has a hydrophilic head that is in contact with the water and a center of hydrophobic tails, which can be used to isolate grime.

Soaps are sodium or potassium fatty acids salts, produced from the hydrolysis of fats in a chemical reaction called saponification. Each soap molecule has a long hydrocarbon chain, sometimes called its 'tail', with a carboxylate 'head'. In water, the sodium or potassium ions float free, leaving a negatively-charged head.


Soap is an excellent cleanser because of its ability to act as an emulsifying agent. An emulsifier is capable of dispersing one liquid into another immiscible liquid. This means that while oil (which attracts dirt) doesn't naturally mix with water, soap can suspend oil/dirt in such a way that it can be removed.

The organic part of a natural soap is a negatively-charged, polar molecule. Its hydrophilic (water-loving) carboxylate group (-CO2) interacts with water molecules via ion-dipole interactions and hydrogen bonding. The hydrophobic (water-fearing) part of a soap molecule, its long, nonpolar hydrocarbon chain, does not interact with water molecules. The hydrocarbon chains are attracted to each other by dispersion forces and cluster together, forming structures called micelles. In these micelles, the carboxylate groups form a negatively-charged spherical surface, with the hydrocarbon chains inside the sphere. Because they are negatively charged, soap micelles repel each other and remain dispersed in water.

Grease and oil are nonpolar and insoluble in water. When soap and soiling oils are mixed, the nonpolar hydrocarbon portion of the micelles break up the nonpolar oil molecules. A different type of micelle then forms, with nonpolar soiling molecules in the center. Thus, grease and oil and the 'dirt' attached to them are caught inside the micelle and can be rinsed away.

Although soaps are excellent cleansers, they do have disadvantages. As salts of weak acids, they are converted by mineral acids into free fatty acids:

CH3(CH2)16CO2-Na+ + HCl → CH3(CH2)16CO2H + Na+ + Cl-
These fatty acids are less soluble than the sodium or potassium salts and form a precipitate or soap scum. Because of this, soaps are ineffective in acidic water. Also, soaps form insoluble salts in hard water, such as water containing magnesium, calcium, or iron.

2 CH3(CH2)16CO2-Na+ + Mg2+ → [CH3(CH2)16CO2-]2Mg2+ + 2 Na+

The insoluble salts form bathtub rings, leave films that reduce hair luster, and gray/roughen textiles after repeated washings. Synthetic detergents, however, may be soluble in both acidic and alkaline solutions and don't form insoluble precipitates in hard water. But that is a different story...

What is a Tsunami and What Causes Them?

What is a Tsunami and What Causes Them?

Tsunami, which is a Japanese word translated through English into “harbor wave,” is an enormous and destructive wave that scientists referred to as “seismic sea waves.” Many people may know tsunamis by their layman term, “tidal wave” (Dudley, p.28; Cook). Tsunamis are most common in the Pacific Ocean, specifically near Japan where they frequently wreak havoc on its harbors and coastal villages (Dudley, p.28). Tsunamis are in fact a series of extremely long waves that are primarily associated with earthquakes and coastal regions. However, landslides, volcanic eruptions, and even impacts of objects from outer space like asteroids and meteors can cause tsunamis. Tsunamis can reach speeds exceeding 600 mph and even in shallow waters reach heights of over 100 feet (NOAA). Tsunamis have in fact been reported since ancient times, with the first recorded tsunami occurring off the coast of Syria in 2000 B.C. (Lander, 1)

Tsunamis are caused by violent movement on the seafloor. Their generation is due to the ocean’s bottom rising or dropping, which displaces the column of water directly above it. This is most common in large subduction zones, where the collision of two tectonic plates causes the oceanic plate to dip beneath the continental crust (Lander, p.2). This movement on the seafloor can be caused by three different types of geologic activity. The first and most common is submarine faulting (as mentioned above), which actually causes earthquakes and tsunamis. It was originally believed that the earthquakes themselves were the cause of tsunamis, but that hypothesis has been revised (Dudley, p.33). The second most common geologic activity is a landslide. If a landslide were to start out above sea level and plunge into the sea a tsunami might occur. Also, tsunamis can be generated if a landslide occurs underwater. The third cause of tsunamis is volcanic activity. The production of tsunamis in this circumstance is quite similar to that of tsunamis caused by submarine faulting. An explosion of a submarine or shoreline volcano can generate a tsunami, as evidenced by the explosion of the island volcano Krakatoa in 1883 that killed over 36,000 people in Java and Sumatra (Dudley, p.34).

It should come as no surprise than that the Pacific Ocean is a source of the vast majority of tsunamis. This area is one of the most geologically active in the world, as the Pacific Ocean basin is surrounded by deep ocean trenches, explosive volcanic islands, and mountain ranges as well as the frequent earthquakes and volcanic eruptions that occur nearby 


Now that you know what a tsunami is, it’s time to scare you with the terrifying results of what happens when a tsunami hits land!






Three types of Tsunami