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What two factors determine whether or not a molecule is polar?

Polar bonds are formed when one atom in the bond has a much stronger pull towards electrons than the other atom. The difference in strength can be predicted by comparing electronegativity values. If one electronegativity value is higher, that atom will pull the electron closer and develop a slightly negative charge, while the other atom develops a slightly positive charge.

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What is the formula for calculation of deceleration?

One formula to calculate deceleration is a = (v - u)/t, where a is the deceleration, v is the final velocity, u is initial velocity and t is the time taken. If distance covered is known but time passed is not known, a second formula that can be used is a = (v^2 - u^2) / (2s), where a is the deceleration, v is final velocity, u is initial velocity and s is the distance covered. The deceleration formulas calculate the rate of decrease in overall speed. Deceleration is typically measured in meters per second^2, or other distance per time unit squared units.

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What elements make up paper?

The trees are ground into chips and then boiled to remove lignin, a substance that holds together the cellulose monomers responsible for the structural support of the trees. The cellulose is then made into liquid paper pulp, dried and shipped to be made into paper.\nThe different chemicals that are then added give the final paper its unique qualities. Sodium aluminate is used in combination with alum to control pH. Silicate of magnesia is used to give paper a greasy or soapy feel and enables paper to take a high finish. Barium sulfate, cadmium sulfide, calcium sulfite and lead chromate are all..

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Why does the moon change colors?

The moon tends to look more reddish when it is closer to the horizon because its light must pass through heavier atmosphere. Once it has risen directly overhead, it looks more yellow or white. The same process occurs with the sun when it rises. During the day, the moon must also compete with sunlight being scattered through the atmosphere, which causes it to appear to be white.

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What are the bonds between adjacent water molecules?

A hydrogen bond occurs when the hydrogen of one molecule of water attracts the oxygen atom of another. This occurs because of the differences in electronegativity between hydrogen and oxygen. Oxygen is the more electronegative atom, which means it has a stronger attraction for electrons. Hydrogen has a much lower affinity for electrons.\nWhen hydrogen and oxygen bond, the electrons that are shared between them orbit around the oxygen atom for longer periods than around the two hydrogen atoms. This unequal sharing causes hydrogen to take on a partial positive charge, whereas oxygen becomes slig..

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Which is more dangerous, tornadoes or hurricanes?

Hurricanes generally causes more damage overall once they make it onto land. Instead of the relatively tiny areas that tornadoes affect, hurricanes can affect thousands of square miles over several days, bringing storm surges and flooding rains with them. They can also spawn small tornadoes. Tornadoes, on the other hand, spring up with little warning, hit very small areas very hard and then dissipate fairly quickly.

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When can Jupiter be seen at night?

In order to get a good look at Jupiter, using a telescope and binoculars is recommended. On a clear night far away from city lights, Jupiter can be seen shining brightly throughout the night until it sets in the northwest direction at around 3:00 a.m. EDT. If using a telescope, one of Jupiter's four moons may also be seen.

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What is an example of a reflex action?

Normally, the brain coordinates a response to any stimulus via the spinal cord and the central nervous system. In certain circumstances, the brain is bypassed for a very quick response. A response takes longer when the brain, the nerves and the spinal cord are involved.\nAll reflex actions occur very quickly without any thinking. The action is not premeditated, and this makes it instantaneous. The pathways that cause a reflex action are called reflex arcs. These arcs consist of a sensory nerve, neurons or nerve cells and a motor nerve. Neurons are like sensory pathways. Millions of neurons are..

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Who discovered the first constellation?

Many of the constellation names still in use as of 2014 have their roots in Greek astronomy, which was based on the constellations of the Mesopotamians; some even use translations of the names applied by the Mesopotamians. The Babylonians also kept records of constellations. Because the Greeks could not see stars in the Southern Hemisphere, some of these constellations were not named until the 16th century.

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What is hematopoiesis?

The process of hematopoiesis ultimately results in the production of mature or fully-formed white blood cells, red blood cells and blood platelets, which help to control and stop bleeding following injuries. Throughout the process, blood cells of all three kinds develop, differentiate, and finally emerge as mature cells. During their growth stages, all cells go through multiple transformative stages, often undergoing at least five cell divisions. Each division produces more cells, enabling the process to continue. Hematopoiesis enables the body's cells to perform important tasks such as r..

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