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What is all matter in the universe composed of?

Atomic theory has been refined since Democritus's time, taking its greatest leap between 1789 and 1803. During that time, three primary laws of atomic theory were developed. These include the Law of Conservation of Mass, the Law of Definite Proportions and the Law of Multiple Proportions.\nThe first is credited to Antoine Lavoisier, and states that the mass involved in any chemical reaction remains constant. Joseph Louis Proust proved the second law in 1799, which states that regardless of their original source or quantity, if a compound is reduced to its base elements, the mass of those ..

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Does the moon have an atmosphere?

As of 2014, scientists are not entirely certain of the composition of the moon's atmosphere. NASA researchers began to glean insight into its composition in 1972 during the Apollo 17 mission, when astronauts deployed the Lunar Atmospheric Composition Experiment. In addition to confirmed detections of helium and argon, LACE may also have detected neon, ammonia, methane and carbon dioxide in comparatively smaller amounts in the moon’s atmosphere. Ground-based instruments have also detected sodium and potassium in the moon’s atmosphere.\nMore recently, NASA’s Lunar Reconnaissance Orbit..

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Which metal has the larger radius: lithium or sodium?

On the periodic table, atomic radius increases both from left to right and from top to bottom. The first element on the table, hydrogen, has the lowest atomic radius, while those in the bottom-right corner have the highest radius.\nBoth lithium and sodium are members of the alkali metals group, which also includes potassium, rubidium, cesium and francium. Of these elements, lithium has the smallest atomic radius and francium has the largest.

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How did the universe begin?

At the time of the Big Bang, the universe and all of its matter was concentrated in a single point. As the Big Bang started, this matter was heated to very high temperatures and expanded rapidly.\nSeveral scientific observations have convinced astronomers that the Big Bang theory is correct. One of the strongest pieces of evidence is called the cosmic microwave background, or CMBR. This is the remaining heat from the Big Bang that can be seen in all directions when looking into the universe. As the universe has expanded, the initially hot material has cooled, so that it now emits light as micr..

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What is geothermal power?

The extreme heat caused by magma within the Earth's crust is a major form of geothermal power. It is harnessed by large power plants and used to provide electricity to communities. These plants use steam to power a turbine, which creates electricity. Since mild geothermal energy can be found as little as 10 feet underground, it is also used directly to heat homes, greenhouses and other buildings by way of a ground-source pump.

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In what year was Venus discovered?

It is easy to see Venus with the naked eye. Next to the moon, it is the brightest object in the night sky. People in the old days referred to Venus as the "morning star" when seeing it in the morning and called it the "evening star" when seeing it at night. They did not know that the celestial object they were viewing was actually the planet Venus.

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What are the two types of sweat glands?

Eccrine sweat glands are primarily located on the palms of the hands, the soles of the feet and the forehead. Sweat glands are used by the body to lower the body temperature. Sweating can also be a response to nerve stimulation. The amount of sweat that the glands produce varies from person to person. Sweat glands end in hair follicles or pores. The two different types of sweat glands vary in size and are activated at different ages.

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How is a ruler used?

Most professionals recommend lining up the object or line that is to be measured with one end at zero, which is found at the left end. Some rulers are quite stiff as they are made from wood or plastic, which makes it difficult to wrap them around objects if they are to be measured; however, there are also some that are made from more flexible materials. There are also printable rulers that are available online.Regardless of whether an individual has measured in centimeters or inches, both of these measurements are interchangeable and can be easily converted. There are 2.54 centimeters in each ..

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When did Pluto become a dwarf planet?

Dwarf planets are much the same as their larger cousins; they share the same physical and chemical compositions and go through the same life processes, from formation through maturity and eventually death. However, according to National Geographic, the primary difference between dwarf planets and regular planets is that dwarf planets do not "clear the neighborhood" around their orbits. This means that they never become gravitationally dominant, and share their orbital spaces with celestial bodies of similar sizes. Pluto classifies as a dwarf planet because it shadows Neptune, the closest regul..

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What elements are found in lipids?

Fatty acids, soaps, detergents, oils, phospholipids, steroids, fat-soluble vitamins and terpenes are the most common kind of lipids. Fatty acids are long chains that are created by the process of hydrolysis. The unique structure of a fatty acid gives it a distinct melting point.Lipids are able to store energy for a cell, signal cellular responses and provide structure to the membranes of the cell.

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