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Energetics and Thermodynamics

heat released for every 1.00 g of sucrose oxidation

determine how much heat is released for every 1.00 g of sucrose oxidized from the following: Sucrose C12H22O11 is oxidized in the body by O2 that ultimately produces CO2(g) and H2O (g) and releases 5.64 E3 kJ/mol sucrose. This is what I come up with for the balanced equation: 1 C12H22O11 (s) + 12 O2 (g) ----- 12 CO2 (

Calculate Energy Required

The specific heat of fusion of silver is 30.0 calories per gram and the specific heat of silver is 0.30 Joules per gram per degree C. Calculate the energy required to melt 5.0 moles of silver if it starts as a solid at 25 degree C below its normal melting point and is heated to exactly 0.01 Celsius degree above its normal meltin

Increase in Entropy

Thinking about entropy as disordered states, which of the following reactions would show an increase in entropy? Mark those in which entropy increases as TRUE. None of these reactions are balanced. H2 + O2 → H2O 1. True 2. False CaCO3 → CaO + CO2 1. True 2. False H2O(l) → H2O

Metals and Water

Which of the following metals would be the least safe to drop in water? Why? A. lithium B. magnesium C. iron D. potassium E. aluminum.


In a particular reaction, the system does work on the surroundings and absorbs heat rom the surroundings. What is the sign of the internal energy change, ^U? A. always negative B. always positive C. positive or negative depending on the relative magnitudes of the energy transfers D. always zero


The correct equation for which the enthalpy change defines the standard enthalpy of formation for C2H5OH (l) is : A. CH2 + CH2 + H2O -->CH3CH2OH B. CH3CHO + H2 -->CH3CH2OH C. 4 C + 6 H2 + O2 --> 2 CH3CH2OH D. 2C + 3H2 + 1/2 O2 -->2 C2H5OH E. 2C + 6H + O --> C2H5OH


For the following reaction, what is the enthalpy of cyclization per mole of actylene? 3C2H2 (g) --> C6H6 (l) ^H = -630 kJ A. 210 kJ/mol C2H2 B. -630 kJ/mol C2H2 C. 0 kJ/mol C2H2 D. -210 kJ/mol C2H2 E. -1890 kJ/mol C2H2


At 25 degrees C and constant pressure, carbon monoxide gas combines with oxygen gas to give carbon dioxide gas with the evolution of 10.1 kJ per gram of carbon monoxide consumed. What is the value of ^H for the balanced reaction? A. -566 kJ/MOL B. -283 kJ/MOL C. 283 kJ.MOL D. 141 kJ/MOL E. -141 kJ/MOL


What mass of oxygen gas, measured at 238 K and 3.51 atm, is required in ordered to release 6670 kJ of heat to the surroundings? CH4 + 2O2 --> CO2 + 2H20 ^H = 890.3 kJ A. 240 B. 6260 C. 0.574 D. 479 E. 7.49


Calculate the heat capacity of a sample of radiator coolant if a temperature rise from -5 degrees C to 142 degrees C requires 932J of heat? A. 0.158 J/C B. 1.37 x 10 to the power of 5 J/C C. 6.80 J/C D. 6.56 J/C E. 6.34 J/C

Specific Heat and Calculating Final Temperatures

A 15.) g block of aluminum at an initial temperature of 27 C absorbs 0.678 kJ of heat. What is the final temperature of the block? The specific heat of Al is 0.902 J g-1C-1. A. 50.1 C B. 38.6 C C 54.5 C D. 68.6 C E. 77.6 C.

Specific Heat: Heat Absorbed by Copper

Copper clips are sometimes used as "heat sinks." How many grams of copper must be in contact with an electric component to absorb 10.0 J of heat and not let the temperature increase by more than 40 C? The specific heat of copper is 0.385 J/g K.


Calcium carbide (CaC2) reacts with water to form acetylene (C2H2), a gas used as a fuel in welding: CaC2 + 2H2O ==> C2H2 + Ca(OH)2 ^H = 128.0 kJ How many kilograms of CaC2 are consumed in a raction that releases 3.64 x 104 kJ of heat under these conditions? A. 1.82 x 10 to the power of 4 kg B. 284 jg C. -18.2 kg D

specific heat of aluminum

The specific heat of aluminum is 0.902 J g-1 C-1 at 25 C. How much heat, in kJ, does it take to raise the temperature of a 12.0 g chunk of aluminum from 15.5 C to 35.5 C? A. 0.216 kJ B. 0.0108 kJ C. 0.0180 kj D. 240 kJ E. 216 kJ

Heat applied to water and alcohol

Which of the following liquids has the highest specific heat capacity? water, alcohol, glycerine, or hexane. If you applied equal amounts of heat to equal masses of water and alcohol, which will stay closest to its initial temperature?


A burner on an electric range has a heat capacity of 345 J/K. What is the value of q (heat released) in kilojoules, as the burner cools from temperature of 467 degrees celsius to 23 degrees celsius. A. -153 kJ B. +153 kJ C. -531 kJ D. -431 kJ



the heat capacity of this calorimeter

When using a calorimeter to do detailed heat calculations, you must determine the heat capacity of the individual calorimeter you use as a calibration factor for later experiments. The fluid in a bomb calorimeter was heated for 568 seconds with a 15.00-watt heater. The temperature of the calorimeter fluid increased by 2.00 deg

Specific Heat: Temperature of the Coffee Cup After Adding Gold

A jeweler heats 60 g of gold (about 2 oz) almost to melting, 1000 degrees Celsius and drops it a cold cup of coffee to heat it up. If the cup has 200 ml of liquid in it (treat it as pure water) and is at 25 degrees Celsius before the hot gold is dropped in, estimate the temperature after the gold has been added. The specific hea

Calorie and Specific Heat of Water

The calorie is an energy unit equal to about 4.2 joules. It is defined as the amount of heat required to raise one gram of water by one degree Celsius. An average person has a mass of around 68 kg. About how much energy would be required to raise an equal mass amount of water from room temperature (24 degrees celsius) to body

Balanced Equation

The decomposition of solid potassium chlorate by heating yields solid potassium chloride and oxygen gas products. Write a balanced equation for this reaction.

Reactions in Spectroscopy

1. Before spectroscopy was invented, Korner's absolute method was used to determine whether a disubstituted benzene derivative was the ortho, meta, or para isomer. Korner's method involves adding a third group (often a nitro group) and determining how many isomers are formed. A turn-of-the-century chemist isolated an aromat


General Information: The recrystallized adduct appeared as white, thin, long crystals weighing 0.3606 g and with a melting point of 123-126C. Based on the melting point ranges of the adduct sample, it was concluded that the unknown diene was alpha-phellandrene. DIRECTIONS: 1. DRAW the structure of the alpha-phellandr

Dimensional analysis

If an aluminum sphere has a mass of 23.01 grams and was heated to 137.0 Celsius and lowered into a cup containing 20.00 mL of water at 21.0 Celsius. The final temperature of the water and the sphere was 44.0 Celsius assuming no heat was loss calculate the specific heat of the aluminum in the sphere. C h2o =4.184J/g-0celsius

balanced reaction equations and net ionic equations

Write the balanced formulas for the reactants and predicted products for the chemical reactions that follow. Also include net ionic equations. a.) A solution of formic acid, HCOOH, is oxidized by an acidified solution of potassium dichromate. b.) Concentrated hydrochloric acid solution is added to solid manganese(IV) oxide a

Using Hess's Laws in Various Equations

1.) Given the following data: Fe2O3(s) + 3CO(g) ---- 2Fe(s) + 3CO2(g) delta H = -23 kJ 3Fe2O3(s) + CO(g) ----- 2Fe3O4(s) + CO2(g) delta H = -39 kJ Fe3O4(s) + CO(g) ----- 3FeO(s) + CO2(g) delta H = +18 kJ Calculate delta H for the reaction FeO(s) + CO(g) ----- Fe(s) +CO2(g) 2.) At 298

heat of combustion for the reaction

1.) Calculate the heat of combustion for the reaction in which ethane combines with oxyen to give carbon dioxide and water vapor. C2H6 + 7/2 O2 ----- 2CO2 + 3H2O a.) 2C(s) + 3H2(g) ----- C2H6(g) delta H = -20.2 Kcal b.) C(s) + O2 (g) ------- CO2(g) delta H = -94.0 Kcal c.) H2(g) + 1/2 O2 ----- H2O(g) delt

Thermochemistry - Heat of Reaction

1.) The specific heat of a solution is 4.18 J/(grams x degrees Celsius) and its density is 1.02 g/mL. The solution is formed by combining 20.0 mL of solution A with 30.0 mL of solution B, both initially at 21.4 degrees Celsius. The final temperature is 25.3 degrees Celsius. Calculate the heat of reaction. assuming no heat i