Master Chemistry with Fun Quizzes & Brain Teasers!

A chemist determined by measurements that 0.0750 moles of magnesium participated in a chemical reaction. calculate the mass of magnesium that participated in the chemical reaction.
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Please helpBoiling off a pot of waterA pot containing 500 g of water is brought to a boil. The latent heat of vaporization is for water Hv =2260 kJ/kgHow much heat will it take to completely boil the water (turn it all to steam). Use the equation q = mHv
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How many moles of gas occupy 128L at a pressure of 4. 2 atm and a temperature of 382K
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ENDOTHERMICDuring this chemical reaction energy is absorbed. In the chemistry lab, this would be indicated by a decrease in temperature or if the reaction took place in a test tube, the test tube would feel colder to the touch. Reactions like this one absorb energy because The reactants have less potential energy than the products
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A 1500. 0 gram piece of wood with a specific heat capacity of 1. 8 g/JxC absorbs 67,500 Joules of heat. If the final temperature of the wood is 57C, what is the initial temperature of the wood?
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The mass of marshmallow and a food holder weighs 5. 08 g. After burning the marshmallow, the marshmallow and food holder have a mass of 5. 00 g. Determine the mass of food burned. (Don't forget units. )
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You have twisted your ankle and need to apply a cold pack. You squeeze the bag and as the chemical reaction occurs, you can feel that the pack is getting colder. How would you classify this type of reaction? Using what you understand from our lessons in unit 4, explain how the heat transfers between the cold pack and your skin? Also, describe how the law of conservation of energy applies to this system
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To what pressure must a gas be compressed in order to get into a 3. 00L the entire weight of a gas that occupies 350. 0L at standard pressure?
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A 98. 5C metal bolt is placed in a calorimeter of 23. 1C water. Which way will the heat energy flow?
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An ethanol plant distills alcohol from corn. The distiller processes 2. 0 t/h of feed containing 15% alcohol and 82% water; the rest is inert material. The bottoms (waste) produced is 85% of the feed and contains 94% water, 3. 5% inert material, and 2. 5% alcohol. The vapor (product) from the top of the distiller is passed through a condenser and cooled to produce the final product. Determine the rate of production of the final product and its composition
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1.85 l of a gas is collected over water at 98.0 kpa and 22.0 c. what is the volume of the dry gas at stp?
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The pressure at the bottom of a lake is 2. 35 atm. If water saturated with oxygen(concentration 0,34 g/L) is carried by a current to to a depth where the solubilityof oxygen is 0. 21 g/L, what is the pressure of the water.
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Reddish-brown colordont need a magnifying glass to see grainsgritty when drysticks to my fingers when wetdoesnt smell like anythingdries quicklydoes not get foamy with vinegardamp soil made a ball but it fell apart quicklyWhat type of soil
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A 3. 00 g mass of compound X was added to 50. 0 g of waterand it is found that the freezing point has decreased by 1. 25 C. What is the molar mass of X if it has a van't Hoff factor of 3?g/mol (Kf of water = 1. 86 K. Kg/mol)Your answer should be rounded to three significant figures. Do not include unitsin your answer.
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Which states in the United States have a longer political history than the others?
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What amount of heat, in kJ, is required to vaporize 181.20 g of ethanol (CHOH)? (Hvap = 43.3 kJ/mol)
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Whichthermochemicalequationcorresponds tothe graph?
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A decomposition of hydrogen peroxide into water and oxygen gas is an exothermic reaction. If the temperature is initially 28 C, what would you expect to see happen to the final temperature?Explain what is happening in terms of energy of the system and the surroundings.
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(marking brainliest!) given the following bond energies: h-h = 436 kj/mol i-i = 151 kj/mol h-i = 297 kj/molcalculate the enthalpy change for the following reaction:h-h + i-i ---> 2h-i-choices are attached!
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A 1500. 0 gram piece of wood with a specific heat capacity of 1. 8 g/JxC absorbs 67,500 Joules of heat. If the final temperature of the wood is 57C, what is the initial temperature of the wood? (2 sig figs)
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How do paleontologists determine the placement of a fossil for display? Explain how diagnostic structure is used for the accurate placement of a fossil
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Explain why I2 is a solid, Br2 is a liquid but Cl2and F2 are gases even though they are all Halogens
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EXPLAIN Describe the patterns you see among the chemical formulas. Howdoes the placement of the elements on the periodic table appear to relate to thenumbers in the chemical formula?PLEASE HELP ME
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Stalactites-the long, icicle-like formations that hang from the ceilings of caves-are formed from recrystallizing minerals such as calcite (calcium carbonate). The Ksp of calcium carbonate is 4. 5 x 10-9. What is the concentration of a saturated calcium carbonate
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