Chemistry

!!!Help ASAP!!!What characterizes a system at equilibrium?A. The system cannot undergo change.B. The system has stopped changing.C. The system is changing at an even rate.D. There is no net change to the system.
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For many purposes we can treat nitrogen as an ideal gas at temperatures above its boiling point of - 196.C. Suppose the temperature of a sample of nitrogen gas is raised from -98.0 C to -89.0 C, and at the same time the pressure is increased by 10.0%. A) Does the volume of the sample increase, decrease, or stay the same?
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Which sentence contains a dependent clause?A.Would you like to see the Washington Monument or the White House?B.For spring break, my family will visit Washington, D.C., which is the capital of the United States.C.The cherry blossom trees in Washington, D.C. are beautiful, so people like to have picnics in the park.D.The Lincoln Memorial was built in 1922, and its one of the most popular monuments in Washington, D.C.
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The nonvolatile, nonelectrolyte sucrose, C12H22O11 (342.3 g/mol), is soluble in water H2O. Calculate the osmotic pressure (in atm) generated when 12.8 grams of sucrose are dissolved in 278 mL of a water solution at 298 K.
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Which are characteristics of medusae?are sessile, have tentacles, mouths open downwardswim freely, lack tentacles, mouths open upwardswim freely, have tentacles, mouths open downwardare sessile, lack tentacles, mouths open upward
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New technologies have allowed buildings to become taller and heavier than ever before.This is an example of:
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Which states of matter can flow?1) gas and liquid 2) gas3) gas, liquid, and solids 4) liquid
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Calculate the fraction of atoms in a sample of argon gas at 400 K that have an energy of 10.0 kJ or greater.
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The human activities in two locations are described below: Location A: Rampant use of plastic containers Location B: Excessive use of pesticides and fertilizers Which statement is most likely true? A. Location A will have poor air quality because plastic is biodegradable. B. Location A will experience water scarcity because plastic absorbs moisture. C. The population of honeybees will increase in Location B because production of crops will increase. D. The population of fish in Location B will decrease because the water is contaminated.
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Use the table to determine the charge of phosphate in K3PO4.
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If you have 120. mL of a 0.100 M TES buffer at pH 7.55 and you add 3.00 mL of 1.00 M HCl, what will be the new pH? (The pKa of TES is 7.55.)
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If a reaction of 5.0 g of hydrogen with 5.0 g of carbon monoxide produced 4.5 g of methanol, what was the percent yield?
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what two quantities does the AVEE measure
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8 oz bottle of Dr. Pepper made with imperial cane sugar (C12H22O11) contains 27 g of sugar in 236.6 mL of water. What is the molarity of the solution with respect to cane sugar?
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3.A gas has a volume of 225 L at 175 K and 150 kPa. What will be its volume at a temperatureof 112 K and pressure remains constant?4.A gas is heated to 180 K at a constant pressure of 1 atm. If the container expands to hold avolume of 44.8 L, what was the volume of the gas, at a temperature of 90 K?A 200 L sample of gas is collected at 50 kPa and a temperature of 271 K. What volumewould this gas occupy at 100 kPa and a temperautre of 14 K?6.Find the new volumes if the values given below change to STP (273 K and 101.3 kPa)...(a) 24.6 L at 25C and 10 atm
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Calculate the speed of sound at 288 K in hydrogen, helium, and nitrogen. Under what conditions will the speed of sound in hydrogen be equal to that in helium?
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the temperature of a sample of copper increased by 23.0 C when 265 J of heat was applied. What is the mass of the sample?
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Potassium nitrate has a lattice energy of -163.8 kcal/mol and a heat of hydration of -155.5 kcal/mol.How much potassium nitrate has to dissolve in water to absorb 101 kJ of heat?
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How many unhybridized p atomic orbitals are present when a central atom exhibits trigonal planar geometry?
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As space exploration increases, means of communication with humans and probes on other planets are being developed. (a) How much time (in s) does it take for a radio wave of frequency 8.93 x 10 s to reach Mars, which is 8.1 x 10 km from Earth? (b) If it takes this radiation 1.2 s to reach the Moon, how far (in m) is the Moon from Earth?
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You measure 3.03 mL of a 50% NaOH solution by weight (its density is 1.53 g mL-1) and dilute it to 500 mL total volume. What is the concentration of this NaOH solution? Write your answer to four decimal places (X.XXXX).
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The atomic masses of two isotopes of silver are 105 and 111. The chemical symbol for silver is Ag. (a) What are the number of protons and neutrons in each of the two isotopes?(b) What is the number of orbiting electrons in each of the two isotopes when each is electrically neutral?
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Suppose you have 75 gas-phase molecules of methanol (CH3OH) at T = 470 K. These molecules are contained in a spherical container of volume 0.500 liters.At this temperature, the root mean square speed of methanol molecules is 605 m/sec.What is the average pressure in the container due to these 75 molecules?(The molar mass of methanol is 32.0 g/mol.)
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how many nanometers in 0.058 km
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