Master Chemistry with Fun Quizzes & Brain Teasers!

How many grams of calcium oxide will be produced in a closed vessel containing 20. 0 kg of calcium and 20. 0 kg of oxygen gas if the reaction goes to completion?2Ca(s)+0 (g) 2CaO(s)
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A 100ml sample of 0.40m hydrofluoric acid is mixed with 100ml of 0.40m lithium hydroxide. will the ph of the final solution be less than 7, equal to 7, or greater than 7
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(07. 05 MC)The volume of a reaction vessel with gaseous reactants is lowered to one-fourth of its original volume. What will happen to the rate of the reaction?It will increase because the concentration of the reactants increases. It will decrease because the concentration of the reactants decreases. It will increase because the gaseous particles are moved farther apart. It will decrease because the gaseous particles are brought closer together
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A sample of gas initially at 1. 4 atm and occupies 720 ml whats the final pressure in atm when the volume changes to 820 mL?
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When 21.44 moles of si react with 17.62 moles of n2 how many moles of si3n4 are formed
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Calculate the moles of barium phosphate that will react with 1.60 g of aluminum hydroxide. you need to write and balance the equation, then solve it.
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Calculate the grams of solute required to make 250 mL of 0. 10% magnesium phosphate (m/v)
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How does latitude affect climate?AThe closer to the poles, the warmer it gets.BThe closer to the equator, the warmer it gets.CThe higher you go up a mountain, the colder it gets.DThe higher you go up a mountain, the warmer it gets.
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1. What is the percent of NaCl in a mixture that contains 23.5 g of NaCl and 212 g of water? Enteranswers in 2 decimal places
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According to the following synthesis reaction determine how many grams of fe2o3 are formed when 16.7 g of fe reacts completely with excess o2. 4fe+3o2 > fe2o3
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An element has similar chemical properties as oxygen and selenium. it has an atomic number greater than oxygen but less than argon. use the periodic table to identify the element and explain how you determined the element using these clues. (write the element name in all lower case. spelling counts.)
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Imagine a piston with an external pressure of 1 bar that contains liquid water, water vapor, and nitrogen gas. the piston is in thermal contact with a large reservoir held at 270.15 k. initially the partial pressure of water vapor in the piston is 489 pa; nothing changes for a long time. at some point the water crystallizes and the system comes to a new equilibrium; the new partial pressure of water vapor in the piston is 475 pa. calculate the difference in the chemical potential for liquid and crystalline water at 270.15 k. (to think about: does the sign of your answer make sense
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From the following data, determine the order of the reaction in ligand and substrate, and write the rate equation. [substrate] (m) [ligand] (m) rate (ms^-1)5 1.0 1.0 5.0 10.0 25 1.0 200 2.0 find the msds for decahydronaphthalene.
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Some breeds of beef cattle have two color coat color options, red and black, where black is dominant over red. If a black bull (male, Bb) is bred to a red cow (female, bb) what are the predicted coat colors of their offspring?A:100% of the calves will be black B:100% of the calves will be redC:75% of the calves will be black, 25% will be redD:50% of the calves will be red, 50% of the calves will be black
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Which has more particles a teaspoon of salt or teaspoon of sugar
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Determine the mass of ammonium chloride, NH4Cl, required to prepare 0. 250 L of a 0. 35 M solution of ammonium chloride
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Explain your thinking. describe the "rule" or reasoning you used to decide if something is a plant.
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The space between the particles of matter in a dead star is. ?
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A 0. 515 g sample of CaCl2 reacts with aqueous sodium phosphate to give 0. 484 g Ca3(PO4)2. Show the calculation for the theoretical yield of Ca3(PO4)2. What is the percent yield of Ca3(PO4)2.
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1. write the balanced net ionic equation for the reactionca2+(aq) + oh-(aq) + h+ + po3-(aq) > ca2+(aq) + po3-(aq) + h2o(l)
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If a substance has a bitter taste, feels slippery , conducts electricity, and has a high pH, it is a ?
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2. Dragonflies can travel at speeds up to 35 miles perhour. How many meters per second is that? (1 mile = 1609 meters) 3. The Hyperion is the tallest redwood tree in the worldat 379. 7 feet. How many centimeters is that? (1 inch = 2. 54 cm) 4. How many atoms are in 2. 35 moles sulfur? 5. How many molecules are in 3. 45 moles sucrose?Pls Help ASAP!
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Methane (CH4) is a common fuel to heat homes in the winter. What is the molar enthalpy of combustion of methane? Assume this combustion occurs entirely in the gas phase. Bond Enthalpies(in kJ mol1):CC: 347 CH: 413 HH:432 OH: 467 C=C: 614C=O: 745O=O: 498A)710kJ mol1B)297 kJmol1C)1843 kJmol1D)+792 kJmol1E)+567 kJmol
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On your own: For further practice, click New sample. In this set, the contents of every tube is randomized. You may even find new substances you havent seen before. Record your observations and make hypotheses about the contents of each tube. Good luck!
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