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    Energetics and Thermodynamics

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    Metal Heating

    Given that: Initial temperature of metal: 20c Final temperature of metal: 100c Initial temperature of water from calorimeter: 20c Final water temperature from calorimeter: 28c 1. What is estimate of specific heat for metal? (use 1 cal/gm°C for water) 2. What is estimate the atomic weight of metal?

    Hydrate Formula and Gravimetric of Cloride

    1. Given that moles of water loss = Weight of water / GMW H2O (=18.051 ) and moles of CuSO4 = final weight/ GMW CuSO4 (=159.61) :Initial Weight: 116.877g (cooper II sulfate hydrate 30g + water ) :Final Weight: 19.177g (after heat compound with burner) :Weight of Water driven off (Initial weight - final weight) : 97.

    Heat Capacity and Calorimetry

    When steam condenses to liquid water, 2.26 kj of heat is released per gram. The heat from 168g of steam is used to heat a room containing 6.44 x 10 to the 4th grams of air (20ft x 12 ft x 8 ft). The specific heat of air at normal pressure is 1.015 j/(g.C). What is the change in air temperature, assuming the heat from the stea

    Identifying the Mechanism and Synthesis

    When J and K are placed in a solution of sodium methoxide and methanol, a new compound, L, is produced. What is the structure of L? Provide a reasonable mechanism for this transformation. (b) Provide a reasonable mechanism for the conversion of L to M, carbon dioxide and acetone. In both mechanisms be sure to indicate which reac

    Mechanisms - reversible reactions

    When (1) and (2) are placed in a solution of sodium methoxide and methanol, (3) is formed. What is the structure of (3)? Provide a DETAILED mechanism for this reaction. Provide a DETAILED mechanism for the conversion of (3) to (4), carbon dioxide and acetone. In both mechanisms, indicate which reactions are reversible. Ple

    Calorimetry

    In a coffee-cup calorimeter, 1.10 g of NH4NO3 is mixed with 76.0 g of water at an initial temperature of 25.00°C. After dissolution of the salt, the final temperature of the calorimeter contents is 23.93°C. Assuming the solution has a heat capacity of 4.18 J/°C · g and assuming no heat loss to the calorimeter, calculate the

    Calculating enthalpy change

    The bombardier beetle uses an explosive discharge as a defensive measure. The chemical reaction involved is the oxidation of hydroquinone by hydrogen peroxide to produce quinone and water. Please see the attached file for full problem description.

    Enthalpy Change for Dissolution

    In a coffee-cup calorimeter, 1.10 g of NH4NO3 is mixed with 76.0 g of water at an initial temperature of 25.00°C. After dissolution of the salt, the final temperature of the calorimeter contents is 23.93°C. Assuming the solution has a heat capacity of 4.18 J/C/g and assuming no heat loss to the calorimeter, calculate the entha

    Enthalpy

    See attachment Consider the following reaction. CH4(g) + 2 O2(g) CO2(g) + 2 H2O(l) H = -891 kJ Calculate the enthalpy change for each of the following cases. (a) 3.00 g methane is burned in excess oxygen. (b) 3.00 103 L methane gas at 738 torr and 21°C is burned in excess

    Heat capacity

    A 5.00 g sample of aluminum pellets (specific heat capacity = 0.89 J/°C · g) and a 10.00 g sample of iron pellets (specific heat capacity = 0.45 J/°C · g) are heated to 100.0°C. The mixture of hot iron and aluminum is then dropped into 97.7 g of water at 24.2°C. Calculate the final temperature of the metal and water mixtur

    Calculating Specific Heat Capacity

    A piece of chromium metal with a mass of 24.26g is heated in boiling water to 98.3C and then dropped into a coffee-cup calorimeter containing 82.3g of water at 23.3C. When thermal equilibrium is reached, the final temperature is 25.6C. Calculate the specific heat capacity of chromium. You determine that 187 J of heat is requi

    Chemistry Problem Set: Heat Energy and Temperature

    The specific heat capacity of benzene is 1.74J/g*K. What is its molar heat capacity (Jmol*K)? What quanity of heat is required to raise the temperature of 50.00mL of water from 25.52 to 28.75C? The density of water at this temperature is 0.997 g/mL. When 108g of water at a temperature of 22.5C is mixed with 65.1g of wat

    Calorimetry - Finding the Heat

    10g HCl are reacted with an excess of NaOH in a calorimeter surrounded with water. The heat capacity of the calorimeter and water together is 1200 cal/deg. After the reaction takes place, the temperature of the water increases from 27.5oC to 30.6oC. Find the heat of the following reaction:

    General chemistry questions

    23) ....CrOsub2^- + ... OH^-...CrOsub4^2- + ...Hsub2O+ e^- When the equation for the half reaction above is balanced what is the ratio of the coefficient's OH^-: CrOsub2^-? a) 1:1 b) 2:1 c) 3:1 d) 4:1 e) 5:1 24) CuO(s) + Hsub2(g) <--- / ---> Cu(s) + Hsub2O(g) triangle H = -2.0kJ The Substances in

    Word problem - work, power, energy

    Step 1: A 240 horsepower car beginning at a stop goes 1/10 of a mile. At optimum performance, what is the maximum speed in miles per hour the car can reach? Feet per minute? Step 2: How many feet have been traveled in a 240 horsepower car when the speed reaches 35 MPH at optimum performance? what fraction of a mile is that d

    Gas Law Problem

    Nitrogen and Hydrogen gases react to form Ammonia. A closed, rigid cylinder contains a total of 0.750 mol of gas at 25 degrees C and 1.10 atm before the reaction takes place; the mole ratio of hydrogen to nitrogen in the cylinder is 3:2. Determine the temperature and pressure of the gas in the cylinder at the end of the reaction

    Enthalpy of Reaction and Endothermic or Exothermic Assessment

    Write the equation for the combustion of 1 mole of ethanol in oxygen and calculate the enthalpy of reaction for this change given delta Hf(CO2) = -393.7Kj/mol delta Hf(H2O) = -285.9 Kj/mol and delta Hf(C2H5OH)=-227kj/mol. I s the reaction exothermic or endothermic?

    Calculating Mass of Products of a Heating a Hydrated Salt

    The mass of a crucible and a hydrated salt was to be 21.477g. The mass of the crucible and the anhydrous salt was 20.070g. The mass of the crucible was 17.985 g. a) Calculate the mass of the hydrated heated b) Calculate the mass of h2o lost from the hydrate during heating c) Calculate the percent water in the hydrate

    Calculate in kilograms

    Elemental phosphorus is made by heating calcium phosphate with carbon and sand in an electric furnace. What quantity of calcium phosphate, in kilograms, must be used to produce 15.0kg of phosphorus? _________________________________________ kilograms

    Simple Entropy

    Please help with the following problems. A) Define entropy. Why is entropy considered an absolute quantity? B) For each of the pairs of substances below, choose the one expected to have the greater absolute entropy. Explain your answer. Assume 1 mol of each substance. i) Cu(s) or C(graphite) at the same temperatu

    Heat Conversion of Ice to Water

    A sample of water weighing 125g releases 10.0 kcal of heat as it cools from 80.5ºC to 0ºC. It then releases another 10.0 kcal of heat as it freezes at this temperature. How many kcal of heat are needed in order to convert 125g of ice at 0º to water at 80.5ºC?

    Thermodynamic Data and Standard Enthalpy of Decomposition

    Use thermodynamic data to calculate the standard enthalpy of decomposition of liquid hydrogen peroxide into water and oxygen gas: H2O2(l)-->H2O(g) + 1/2 O2(g). Calculate the energy released by the decomposition of 1.0 g of 90% hydrogen peroxide solution. Molar mass of hydrogen peroxide = 34.0 g/mol. Estimate the final temperat