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une the folowing model to answer go C. man many lone pain are found in the model above? dot (P): A. 1 6. How many bonding electrons are four.2 the model above? A. 1 B. 3 7. How many neutrons does Copper-65 contain? A. 29 8. How many neutrons does Barium-139 contain? B. 36 A. 56 9. How many electrons does strontium contain? B. 137 A. 56 B. 84 10. How many valence electrons does neon have? C. 6 A. 2 B. 4 C. 8 11. Which of the following elements have 7 valence electrons? A. Mn C. F B. N D. Ag 12. How many valence ce electrons are in an atom of sulfur? A. 2 C. 6 B. 16 D. 5 13. How many va valence electrons are in an atom of phosphorus? A. 2 C. 4 B. 3 D. 5 14. Which subatomic particle plays the greatest part in determining the properties of an element? A. proton C. neutron B. electron D. nucleus Determine the number of neutrons in {}^16O A. 4 C. 16 B. 8 D. 24 C. 2 D. C. 2 D. 0 C. 65 D. 92 C. 83 D. 193 C. 38 D. 193

choices provided. Mark your choice on your TypOrade your ZipGrade scannron will be graded. 1. Which type of reaction is the following: 1.i+Cl_(2)arrow A. Decomposition B. Synthesis C. Single Replacement D. Combustion 2. Which type of reaction is the following: KNO_(3)+Caarrow A . Synthesis B. Combustion C. Single Replacement D. Double Replacement 3. Which type of reaction involves two compounds reacting and switching places to form two new compounds? A. Single Replacement B. Synthesis C. Decomposition D. Double Replacement Vhich type of reaction involves a hydrocarbon reacting with elemental oxygen to form ide and water? A.Single Replacement B. Combustion C. Synthesis D. Decomposition

tions: Use the reading below to answer questions 1-4 Reading: Oil Spill in Alaska arch 24, 1989, the tanker Exxon Valdez struck in Alaska's Prince William Sound and spilled Illion gallons of crude oil into the ocean water. sands of birds, otters and seals in the fragile ystems were killed and local economies pndent on tourism and fishing were devastated. spill was met with a massive response and nup crewsjused multiple methods to remove oil the water and beach They collected the oil floating booms, skimmed it from the surface of water, soaked it up with absorbent materials, dispersed It with chemicals. They ssure-washed the beaches and removed contaminated sand with backhoes and tractors. They even tried burning the oil. Scientists also used the opportunity to test a new cleanup strategy. They stimulated naturally occurring bacteria to biodegrade or break down, the oil. These bacteria feed on hydrocarbons produced by trees in the region.The tree hydrocarbons are chemically similar to oil.This process is an example of bioremediation, the attempt to clean up pollution by enhancing natural processes. Cleanup crews were able to clean up some of the oil because it did not mix with the water. What properties of oil and water made this cleanup process possible? A. Water is polar and oil is nonpolar so the oil collected under the water. B. Water is nonpolar and oil is polar so the oil collected under the water. C. Water is nonpolar and oil is polar so they did not mix and the oil floated on the water. D. Water is polar and oil is nonpolar so they did not mix and the oil floated on the water. Scientists used bacteria to biodegrade, or break down , the oil. What type of chemical reaction would this represent? A. Synthesis B. Decomposition C. Single Replacement D. Double Replacement Cleanup crews used many methods to try to clean up the oil Even after eighteen years there is still oil in Princé William Sound. What concept in chemistry explains why the oil has not disappeared? A. Octet Rule B. Nuclear Decay C. Law of Conservation of Mass D. Law of Conservation of Energy Which of the following represents a claim about this article? A. Local economies were devastated. B. The spill was met with a massive response. C. Scientists tested a new cleanup strategy. D. Oil tankers are not safe for the environment.

500 miligramas de cálcio por dia, quando a quantidade recomendada éo dobro . Uma alimentação balanceada é a melhor decisão pra evitar problemas no futuro , como a osteoporose , uma doença que atinge os ossos . Ela se caracterize a pela diminuição substancia I de massa ossea tornando os ossos frágeis e mais suscetiveis ; a fraturas. Disponível em:www.anv isa.gov.br. Acesso em ; 1 ago . 2012 (adaptado) Considerando-se o valor de 6,0times 10^23 mol-1 para a constante de Avogadro , e a massa molar do cálcio igual a 40g/mol qual a quantidade mínima diária de átomos de cálcio a ser ingerida para que uma pessoa supra suas necessidades? 1,5times 10^22 7,5times 10^22 1,5times 10^23 1,5times 10^25 2,5times 10^25 09. 0 brasileiro consome em média in

08. Existe no comércio um produto antimofo constituído por uma embalagem com tampa perfurada contendo cloreto de cálcio anidro. CaCl_(2) . Uma vez aberto o lacre, essa substância I absorve a umidade ambiente , transformandc )-se em cloreto de cálcio di-hidratado, CaCl_(2)cdot 2H_(2)O . Considere a massa molar da água igual a 18g.mol-1 . e a massa molar do cloreto de cálcio anidro igual a 111g.mol-1 . Na hidratação da substânci a presente no antimofo , o ganho percentual , em massa, é mais próximo de 24% 30% 32% 36% 40%