Chemistry

1. An airplane flew from San Francisco to Washington, D.C.Approximately halfway through the flight, the plane had traveled 2,000km in 2.5 hours. What was the speed during this period?
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What process in stars played a role in the formation of the universe?
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in water, what happens to a base? It forms hydrogen ions (H+)It condensesIt evaporates It forms hydroxide ions (OH-)
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Which characteristic most likely describes the water in Lake Taal?Select the correct answer.o The water will appear slightly red.O The water will have a slippery feel.The water will taste bitter.The water will taste sour.
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What is the primary role of the United States Bureau of Counterterrorism?to plan counterterrorist attacksto create active counterterrorism groupsto encourage domestic counterterrorism activitiesto advance counterterrorism efforts in other countries
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A sample of diborane gas has a pressure of 345 torr at a temperature of -15c and volume of 3.48L if conditions are changed so that the temperature is 36c and the pressure is 468 torr what will be the volume of the sample
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How come all skyscrapers don't look alike?
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What is the hydrogen ion concentration [H+] of a HCl solution if the pH is measured to be 2.0?
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(Multiple Choice, 30 pts)A student thinks that halogens are highly reactive because their electrons are weakly attracted to their nuclei. Which is evidence that disputes this student's idea?A. Halogens react with alkali metals.B. Halogens cannot react with noble gases.C. Halogens tend to attract electrons when bonding.D. Halogens have a full octet of electrons.
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PLEASE HURRYWhich substance loses electrons in a chemical reaction?A.the one that is oxidized, which is the oxidizing agentB.the one that is reduced, which is the reducing agentC.the one that is oxidized, which is the reducing agentD.the one that is reduced, which is the oxidizing agent
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A polymer coating of 6:0 mm thickness is cast onto a nonporous flat surface. The coating contains a residual amount of casting solvent, which is uniform at 1.0 wt% within the coating. The mass transfer of solvent through the polymer coating is controlled by molecular diffusion. The air flowing over the coating surface eliminates convective mass-transfer resistances and reduces the solvent vapor concentration in the air to nearly zero. The effective diffusion coefficient of the solvent molecules in the polymer is 2 x 10^-6 cm^2/s.a. How many hours will it take for the solvent concentration at 1.2 mm from the surface to be reduced to 0.035 wt%?
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Water is an example of a
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The periodic table of the elements lists the elements in order of increasing atomic number.Each element has its own unique square in the periodic table.Numbers in an element's square are used to tell how many protons, neutrons and electrons a typical atom of each element has.Based on the information shown, which of the following is true about magnesium atoms?A.They all have 12 protons.B.Some have 24 protons and others do not.C.They all have 24 protons.D.Some have 12 protons and others do not.
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Using Boyle's Law solve the following: An unknown gas has a volume of 200.0 mL and a pressure of 350.0 torr, pressure were increased to 700.0 torr, what is the resulting volume?
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According to one acid-base theory a molecule acts as an acid when the molecule
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A solution with a H+ concentration of 1.00 x 10-7 M is said to be neutral. Why?
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help me name the molecule
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PLZ HELP OR WILL FAIL!!Label A drop downs are: condensation, melting, sublimation Label B drop downs are: condensation, melting, sublimation Label C drop downs are: condensation, melting, sublimation
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what is the atomic number of nickel
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Brandon is trying to remember how the physical and chemical properties of metals, nonmetals, and metalloids compare. He wrote some notes down, then looked in his textbook to see which notes were correct.Which of Brandon's notes, listed below, are correct?I.Metals are the best at conducting heat, and nonmetals are the worst.II.Metals are the worst at conducting electricity, and nonmetals are the best.III.The shape of nonmetals is easy to change, but the shape of metals or metalloids is difficult to change.IV.Nonmetals are dull in appearance while metals are usually shiny.V.Metals tend to have a high density, and nonmetals tend to have a low density.
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I am at the centre of the atom and contain both neutrons and protons. What am I?andComplete the sentence: Atoms have no overall charge because...
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if 31.6 g of KMnO4 is dissolved in enough water to give 160 mL of solution, what is the molarity?ANDwhat mass of oxalic acid , H2C204, is required to make 300 mL of a .74 M solution?
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Is the relationship between the amount of gas and pressure direct or indirect?Explain your answer
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Of the following chemical properties , which one is not one that Covalent compounds DO NOT have ? aThey share electrons between their elements. bThey have weaker bonds. cThey have relatviely higher melting and boiling points. dMany of these compounds are usallly liquids or gases at room temperature.
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