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What do you call a substance that's attracted to water molecules?

Conversely, there are molecules that are not attracted to water at all. These molecules are known as hydrophobic molecules. They cannot form hydrogen bonds and are completely insoluble in water. Hydrophobic molecules are also non-polar, while hydrophilic molecules are always polar. Molecules can be either hydrophobic or hydrophilic based on their atomic arrangement and their polarity. These two classifications of molecules are important in biological processes, since the human body has both hydrophobic and hydrophilic areas.

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How long is a league?

For the Romans, a league was 1.5 Roman miles, which equates to just less than that in English units, 1.4 miles. A Spanish league is equal to 2.6 miles, but the measurement was put out of use in 1568.

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How do you find molar mass?

For many elements, this calculation is simple. Oxygen, for example, has an atomic weight of almost exactly 16. Oxygen forms molecules of two atoms, so the molar mass of O2 is 32 grams per mole. To obtain an absolute mass, it is necessary to know how many atoms are present in a single mole and how many moles are present in the sample.\nTo determine this, it is necessary to apply a function known as Avogadro's Number. This is expressed as an equation, 6.022×10^23, that can be used to compute the number of moles per gram or kilogram. Hydrogen, for example, has an atomic mass of 1. A single ..

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Why does the moon appear to take on a colored hue during an eclipse?

Whenever one celestial body eclipses another, it can create two types of shadow. The penumbral shadow occurs when some of the sun's light is eclipsed, while the umbral shadow represents a complete blockage of the sun's light. For instance, when the moon eclipses the sun, anyone standing in the umbral shadow sees it as a complete eclipse with the sun completely covered by the moon's disc. Those in the penumbra are still able to see the sun's light around the moon's surface.\nSince Earth has an atmosphere, however, light behaves differently when it eclipses the sun. The ..

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What is the structure and function of cells?

The cell wall and membrane offer support and protection to the entire cell. The cell membrane acts as a barrier between the cell and the environment and controls the movements of particles moving in and out of the cell. It also maintains homeostasis.\nThe nucleus controls all cell activities and houses DNA, which is the cell's hereditary material. Cytoplasm is responsible for protecting all of the cell's organelles. Organelles are structures within cells that perform specialized cellular tasks.\nCells also contain mitochondria. These are complex organelles that convert the energy fro..

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What is the melting point of ice?

Knowing the melting points of different substances is important because it can help identify the particular solid, liquid or gas. For example, the element tungsten, which is a metal, has the highest melting point, which is 6,192 degrees.Melting points can also establish the purity of a substance. For example, a mixture has a lower melting point than a pure substance. An example of this is the addition of salt to melt ice.

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How did Joseph Black discover magnesium?

Joseph Black was a student at the University of Edinburg in 1755 when he wrote his findings on magnesium in his thesis, “Experiments upon Magnesia Alba, Quicklime, and Some Other Alcaline Substances.” After Black discovered that magnesium gave off its own gas-lie calcium carbonate when mixed with acid, he heated the acid and magnesium mixture and saw that the magnesium did not bubble and dissolve into the acid. He then mixed it into water and saw that magnesium was not soluble in it.\nHe weighed the magnesium, and when it weighed less, he hypothesized that it was due to the gas it gave off..

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How long does a calf strain take to heal?

The Summit Group explains that a calf strain, commonly known as a "pulled" calf muscle, is a stretch or tear in muscles or tendons. In a typical calf strain, pain is felt immediately, and swelling and bruising often follow. Treatment usually involves applying an ice pack and elevating the injured leg. For severe strains, physical therapy is sometimes needed.

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What are some Artesian water facts?

Bottled before it comes into contact with the air or any possible pollutants, Artesian water has no special medicinal qualities and differs from spring or mineral water only in taste and extraction methods. It is naturally filtered but is not held to any higher safety standards in the United States than tap water. Both, when properly regulated, are equally safe and healthy to drink.\nThere are taste differences between different brands of bottled artesian water, as well, depending on the source and the mineral content. Some artesian water is pure, and some is heavily mineralized.\nArtesian wat..

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What is the distance from the Earth to space?

At an altitude of about 50 to 80 miles, conventional airplanes cannot fly without traveling at orbital velocity. Even at an altitude of about 250 miles above the surface of the Earth, which is the altitude at which the International Space Station orbits the Earth, there are enough air molecules to slow the craft down over time. Periodically, the space station must fire its thrusters to avoid spiraling into the Earth.

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