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Why doesn't convection occur in solids?

In convection, heat is transferred through the mass motion of a fluid. This movement creates heat currents that draw heat in specific directions and allow it to circulate throughout the systems. Liquid and gaseous substances have particles that are free flowing within the substance and allow the currents to travel through without disrupting the overall state of matter. Solids are composed of particles that are tightly packed and do not allow for much motion other than wiggling and collision.\nSolid substances can transfer heat through conduction. Conduction is the process by which agitated par..

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What is a chemical indicator?

Phenolphthalein is a colorless acid. It dissociates in water to form a magenta solution. Adding acid to the solution increases the concentration of positively charged hydrogen ions, shifting the equilibrium of the dissociation of phenolphthalein. With the phenolphthalein no longer dissociated, the pink color disappears. The pH range at which the color change occurs varies by indicator.\nRed cabbage juice is a chemical indicator. It undergoes several color changes as the pH of the solution changes. At a very low pH, the solution is red. As the pH increases, the color changes to pink, then blue,..

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How do you convert square inches to square feet?

Find the conversion valueThere are 12 inches in one foot. In one square foot, there are 144 square inches. The conversion value for square inches to square feet is 144. Divide by the conversion valueTo convert an area measured in square inches into square feet, divide the number of square inches by 144. For example: 200 square inches / 144 = 1.39.Label the answerThe last step in converting square inches to square feet is to label the answer with the correct unit. Continuing with the example, 200 square inches equals 1.39 square feet.

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What are the similarities between plant and animal cells?

Eukaryotic cells, which are plant and animal cells, contain a nucleus, which distinguishes them from more primitive cells, such as those of bacteria. Inside the nucleus, both plant and animal cells have smaller compartments, called the nucleolus. The nucleolus contains the DNA for the plant or animal, and it serves as a set of instructions for building the various proteins that the organism needs. The DNA is usually clustered into groups called chromosomes.\nPlant and animal cells both contain mitochondria. Mitochondria function as the primary energy source for the cell. Mitochondria were prob..

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How does precipitation form?

Rain develops from cloud droplets or ice crystals; if it starts as crystals, the rain first takes the form of snowflakes, but they melt when they enter warmer layers of air, changing into raindrops. In thunderstorms that have a central updraft capable of hosting both rain and snow, snowflakes fall, but the liquid water freezes together with them, making ice pellets that keep growing as they add more water droplets. The updraft then tosses many of the pellets back up, if it is strong enough, and then the pellets fall through again, adding more ice. The stronger the storm, the more times each pe..

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How can a steel ship float?

When ships float on the surface and glide through waves, they displace quite a bit of water. That water must return to its original state and, in doing so, pushes against the passing ship with an upward force.At first, it might not seem possible that a heavy metal like steel can float so easily in the water, but steel ships' ability to float comes from a proper balance between the acting forces of gravity and buoyancy. Gravity does indeed pull downward on the ship, but the equally strong buoyancy force keeps it afloat. The theory behind the buoyancy force comes from the Archimedes' p..

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What are characteristics of green algae?

Green algae is split into the classes Chlorophyceae, Charophyceae and Ulvophyceae. Chlorophyceae contains the most species, and its members have two or more flagella. They also produce a zygospore after sexual reproduction, but they can reproduce asexually. Charophyceae contains asymmetrical cells that may or may not be motile. Its nuclear envelopes dissolve during mitosis, which is different from the other two classes. Ulcophyceae contains mostly marine organisms that reproduce by the alternation of generation.

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What would a solution with a pH of 3 be considered?

The pH scale is used to measure how acidic or basic a substance is. It ranges from 0 to 14. A pH of 7 is neutral. Pure water is an example of a neutral solution. A pH under 7 is acidic. Each whole number below 7 is 10 times more acidic than the number above it. Above 7 are the basic, or alkaline, substances, with each whole number being 10 times more alkaline than the preceding number.

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What is the exchange of genetic material between homologous chromosomes called?

During meiosis I, the chromosomes are replicated. Homologous pairs of chromosomes match up with one another. During this time, parts of the homologous chromosomes overlap; these parts break off and migrate to the other homologs and reattach. These chromosomes are no longer exact duplicates of the original parent chromosomes. Crossing over occurs with such precision that, most of the time, genes do not get lost or become nonfunctional in any way. At times, this process of crossing over is not precise or becomes aberrant. In these cases, the fetus that results is often spontaneously aborted. In ..

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What are the two main groups of minerals?

The oxygen and silicone found in silicates gives these minerals a distinct structure known as the silicone-oxygen tetrahedron. As a whole, the tetrahedron has a negative charge and is able to link with other tetrahedrons.Non-silicates lack the silicone-oxygen tetrahedron and do not possess an identifying formation. The non-silicate groups are created by varying geological processes and contain an assortment of elements that influence the mineral's structure.

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