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What are the defining characteristics of plants within the cactus family?

Since cacti have no leaves, the chlorophyll needed for photosynthesis appears in the stems. Photosynthesis allows plants to make their own food using carbon dioxide, nutrients and water. Using the sun's heat, they turn these items into sugar and oxygen. Most plants take in their carbon dioxide during the day and perform photosynthesis at the same time. Cacti take in carbon dioxide at night and store it until daylight, when photosynthesis occurs. The cooler night temperatures cause less evaporation.\nThe skin surfaces of cacti are often ribbed, which allows the skin to expand without split..

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How fast is lightning?

The speed of a bolt of lightning changes slightly with atmospheric variables such as temperature, pressure and humidity. The flash is the only characteristic of lightning that travels at the speed of light, which is approximately 186,282 miles per second or 670,616,629 miles per hour.\nThe discharge of static electricity can result in many different types of individual lightning bolts. The types of lightning bolts are variations of cloud-to-cloud lightning and cloud-to-ground lightning, such as forked, heat, sheet and ball lightning.

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What is high entropy?

Organization in this case refers to the number of possible ways that particles can be arranged within the confines of a physical system. Particles that are jumbled together can arrive at that state a multitude of different ways, while particles that are arranged in a neat stack can only arrive at that state in one particular way.\nEntropy is tied to the amount of energy in a system because more energetic particles tend to be disarrayed as they move around. Therefore, systems with high entropy also tend to have more energy than systems with less entropy. For example, solid ice water has particl..

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Why are gases compressible?

The initial pressure and temperature of a gas determine how compressible it is. Compressing a gas makes it more dense. Although there is a limit to how much any given gas can be compressed, in general, doubling the pressure on a gas decreases its volume by 50 percent.\nGases also expand easily. All gases expand uniformly to fill any container in which they are placed.

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How did nickel get its name?

Before nickel was discovered by science in the 18th century, the metal was frequently encountered by copper miners digging for ore. These mostly German miners found large masses of what looked like copper ore in the mine. The teams went through great efforts to extract the ore, only to find that they couldn't smelt it properly. When the miners tried to smelt what they thought was copper, they ended up with nothing but a puddle of slag. Thinking that the devil was playing tricks on them to waste their time, the miners came to call the deceitful metal "devil's copper."\nNickel has sinc..

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What is the formula for butanoic acid?

Butanoic acid is a colorless liquid that can be dissolved in water, ether or ethanol. It's a fairly strong acid that can attack metals.\nButanoic acid is used to make esters, which is usually done by replacing the hydrogen molecule in COOH with a carbon atom attached to three hydrogen atoms. Ironically, esters often smell sweet and taste pleasant.

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What is sodium acid pyrophosphate?

Sodium acid pyrosphosphate is widely used in the food industry to maintain the attractive color of canned foods, as a catalyst in chemical conversions and as a lightening agent in potatoes. The U.S. Food and Drug Administration maintains that disodium pyrophosphate does not present a health risk at present levels or foreseeable levels of use.

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What is magnetism?

Magnetism arises from the very structure of the atom. Each atom consists of a nucleus that contains neutral neutrons and positive protons. Negatively charged electrons are constantly in motion around this nucleus, and it is this motion that causes a magnetic field. A good example of magnetism is an electric current, which is essentially the flow of electrons. As electrons flow down a wire, a magnetic field develops around the wire.\nAll materials exhibit some degree of magnetic properties, though some are far more magnetic than others. The degree of magnetism is associated with the degree of m..

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Does magnesium conduct electricity?

A material is considered a conductor or insulator based on how easily current can flow through them. Solid metals, in general, are the best conductors of electricity. Electrons become delocalized in metals due to the fact that they have few valence electrons, usually one to three. This property allows any new electrons introduced to the system, like in the form of electricity, to rapidly move from one atom to the next. Most nonmetals are insulators, except in special forms, like carbon as graphite.

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What are the characteristics of sedimentary rocks?

Sedimentary rocks may be formed through a process called lithification, which is the accumulation and compaction of sedimentary materials into solid rocks. Transportation through water systems such as rivers and oceans may cause clay, silt and other sedimentary materials to accumulate and form into rocks such as sandstone and shale. These rocks typically have smooth and rounded edges due to erosion from constant underwater motion.\nSedimentary rocks may be formed through the chemical dissolving and reforming of materials in rocks. Water sources that have a higher rate of evaporation than preci..

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