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... went straight through the foil did so because the atom is mostly empty space and that the distance between electrons and the nucleus is vast compared to the size of the nucleus itself. In 1919, he discovered the "artificial disintegration" of nitrogen. His experiments show that under alpha radiation, nitrogen is decomposed and hydrogen is formed. Rutherford also devised an electrical method for counting the number of alpha particles emitted from radioactive substances. Using this method, he measured the number of alpha particles expelled per second from one gram of radium to be 34000. Before Rutherford, the smallest particle of matter was represented as a solid ball. Rutherford's experim ...
... NO DEFENCE Areas in Ontario mainly southern regions that are near the Great Lakes, such substances as limestone or other known antacids can neutralize acids entering the body of water thereby protecting it. However, large areas of Ontario that are near the Pre-Cambrian Shield, with quartzite or granite based geology and little top soil, there is not enough buffering capacity to neutralize even small amounts of acid falling on the soil and the lakes. Therefore over time, the basic environment shifts from an alkaline to a acidic one. This is why many lakes in the Muskoka, Haliburton, Algonquin, Parry Sound and Manitoulin districts could lose their fisheries if sulphur emissions ...
... In electrical conductors, these bands are continuous but in insulators and semiconductors there is an "energy gap", in which no electron orbits can exist, between the inner valence band and outer conduction band [Book 1]. Valence electrons help to bind together the atoms in a solid by orbiting 2 adjacent nucleii, while conduction electrons, being less closely bound to the nucleii, are free to move in response to an applied voltage or electric field. The fewer conduction electrons there are, the higher the electrical resistivity of the material. In semiconductors, the materials from which solar sells are made, the energy gap Eg is fairly small. Because of this, electrons in the va ...
... Record the accurate weight below. Product Weight Before Weight After Mass of Test tube + KClO4 41.5g 39.8g Mass of Test tube 37.5g 37.5 Mass of KClO4 4.0g 2.3g 2. Set up the apparatus shown below. 3. Gently heat the test tube containing the potassium perchlorate. Gas should begin to collect in the collection bottle. Record all observation. 4. Once the reaction is complete, no more gas give off, allow the test tube to cool. While the test tube is cooling test the gas in the collection bottle with glowing splint. Caution: Do not leave the rubber tubing down in the water trough during cooling or you will experience back-up. 5. After the test tube has cooled weigh it on a balance. ...
... to fuse at very high temperatures into heavier nuclei, releasing energy and a neutron. In order to squeeze the two nuclei together, an atomic fission bomb is usually used. A fusion reaction releases about four times more energy per unit mass than a fission reaction. The United States supervised the development of the atomic bomb under the code name Manhattan Project, during World War II. The first nuclear chain reaction occurred in December 1942, at the University of Chicago. Soon after the first bomb test, atomic bombs were dropped on the Japanese cities of Hiroshima and Nagasaki in 1945. The first hydrogen bomb was developed by a team of United States scientists and was first tested ...
... Pascal was regarded as a brilliant man of his own time. He made contributions to science, mathematics, and religious philosophy. Pascal was born on June 19, 1623 in Clermont-Ferrand of central France. His father was a highly placed civil official and everyone expected Pascal to follow in his footsteps. But Pascal proved to be a child prodigy. At the age of twelve, he figured out the proposition of Euclidean geometry with no help. At the age of seventeen, he wrote an essay on conic sections which contained a theorum that was named after him. Pascal also invented many things. He constructed the first digital calculating system for his father. He invented the syringe and the hydraulic ...
... This is why we have to do everything we can to save them. The giant panda’s breeding season takes place from March to May. Then the baby pandas are born three to six months later weighing only eighty-five to one hundred forty grams. Two cubs may be born from one mother at the same time, but only one will survive. The reason for this is because one baby panda alone requires a lot of care and two is even harder so usually the mother chooses one and takes care of just that one. Environment: Wild giant pandas are found only in Southwestern China. Giant pandas inhabit damp, misty forests of bamboo and conifers, which are leaves, plants, shrubs, trees, ect. Although giant pandas don’t ...
... Chlamydia prevention and patient care were impeded by the lack of suitable laboratory tests for screening and diagnosis. Such tests are now available. Through education, screening, partner referral, and proper patient care public health workers and health-care practitioners can combine efforts to decrease the morbidity and costs resulting from this infection. Chlamydia is the number one bacterial sexually transmitted disease (STD) in the United States today. Four million new cases of chlamydia occur each year. It is many times more common than gonorrhea. Chlamydia infection is primarily transmitted from person to person through contact with the mucous membranes of the vagina, ure ...
... many cones (Baines, 22). Secondly, acid rain damages the trees through the soil by releasing metals that harm them even further (Lucas, 72). Acid rain makes the trees lose their leaves, so when the trees try to regrow their leaves, buds come instead, this process is called a panic shoot (M. 15). Large land areas which used to be covered with forests are now gone, dead or dying (Baines, 21). Around the 1980’s more than half Kotto 2 of the trees in Germany had signs of acid rain damage (Edmonds, 14). Now it is known that acid rain is one of the biggest contributing factors in the death and deterioration of nature. Lakes suppo ...
... is Panthera and it's species is Tigris Altaica. The Siberian Tiger is a mobile creature and it lives in northern Asia and is found as for north as the Arctic Circle. It's territory is more than four thousand square miles and it will keep that territory indefinitely, as long as the food supply lasts. The Siberian Tiger hunts very much but only about one tenth of the hunts are successful. It requires more than twenty pounds of meat per day. It is heterotrophic and it's diet consists mainly of deer, boar, bear and fish. The Siberian Tiger is a solitary animal. Males and females are only together during mating season. Females will only stay with their litter of two or th ...
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