Chapter TwelveSolutions

An In-Depth Look At the DeAD SeA

Facets of Chemistry

It is a landlocked lake, yet people call it a sea. Certain microscopic bacte-ria seem to thrive in its waters, yet people call it “dead.” Together, these misnomers form the name of one of the most unusual bodies of water—the Dead Sea.

Nestled in the hills of Judea, the Dead Sea lies 418 meters (1371 feet) below sea level, making it the low-est point on the earth (excluding the oceans). It covers an area 67 kilome-ters (42 miles) long and up to 16 kilo- meters (10 miles) wide, encompassing about 647 square kilometers (250 square miles). A peninsula divides the sea into two unequal basins. The large northern basin averages about 396 meters (1300 feet) deep. The smaller southern basin has an average depth of only 6 meters (20 feet).

The Dead Sea receives its water from the Jordan River and four mi-nor streams. The water from these sources picks up many chemicals as it mixes with hot sulfur springs and flows through the region’s salty soil. Unlike many other lakes, the Dead Sea has no outlets. Scorching tem-peratures keep the water level con-stant by evaporating as much as six million tons of water per day. Some-times so much water evaporates that heavy clouds form above the surface of the water. While evaporation re-moves water, it leaves many dissolved minerals behind. Over the centuries, minerals have accumulated and in-creased in concentration. Dissolved minerals now account for nearly 30

percent of the water’s weight. This is seven and one-half times the con-centration of salts in the oceans. The brine is so concentrated that it leaves a feeling of nausea if it is tasted; an oily, slippery feeling if touched; and a white crust of chemicals after it dries. The increased solute content causes the sea to have a much higher densi-ty than other fresh water. This causes some objects to float that would nor-mally sink.

Due to rapid population growth in Israel, Jordan, and the West Bank (which all surround the sea), water that used to supply the Jordan River is now being diverted for drinking water and irrigation. Consequently, the incoming water cannot keep up with the rate of evaporation. The Dead Sea’s depth is currently drop-ping about one meter (3 feet) annual-ly. As a result, the sea is getting saltier and smaller year by year.

The water of the Dead Sea is not evenly mixed. Different areas of water contain different minerals. The upper layer, for example, is rich in sulfates and bicarbonates, whereas the lower zone contains hydrogen sulfide and strong concentrations of magnesium, potassium, chlorine, and bromine. The concentration of salts increases with depth. Concentrated salt solu-tions are denser than pure water, so they sink toward the bottom. Sodium chloride saturates the deep waters of the Dead Sea so much that it remains permanently on the bottom. The floor of the sea is covered with salt

crystals.If the waters of the Dead Sea

could speak, they could add many ex-citing details to biblical history. Much history lies beneath the murky waters of the southern basin. Here the cities of Sodom and Gomorrah once exist-ed. When their wickedness became too great for Jehovah to tolerate, He rained down fire and brimstone (burning sulfur) upon the cities. To-day the waters of the southern basin cover the sites of these ancient cities.

The many valuable chemicals in the Dead Sea’s waters have attracted several mining operations. The area near historical Sodom is now the site of a large chemical industry. The first chemical plant established at Sodom began in 1929. At that time a Jew-ish engineer secured the rights to extract minerals from the Dead Sea. Two years later he marketed the first purified potassium chloride. By World War II, half of Britain’s annual supply of potassium chloride came from this source. Unfortunately, the 1948–49 Arab-Israeli war largely destroyed the chemical plant. In 1952, a new com-pany called the Dead Sea Works, Ltd. was founded. In a greatly expanded operation, it now extracts large quan-tities of chlorides, bromides, chlo-rates, and bromates, as well as many other chemicals from the waters of the Dead Sea. It is also one of the world’s biggest providers of potash for fertilizer production.