Heating and Cooling Curves

The heating curve shown was generated by measuring the heat flow and temperature for a solid as it was heated. The slope of the __________ segment corresponds to the heat capacity of the liquid of the substance.  

Refer to the diagram below for the following questions:    

Refer to the diagram below for the following questions:  

Refer to the diagram below for the following questions:

Describe the (physical/chemical) phenomena exhibited in the following diagram: Where would you place heat of fusion & heat of vaporization in the figure shown?

 Calculate the heat (kJ) evolved when 100.0 g of steam at 130.0  o C is converted to ice at – 5.00 o C

The enthalpy of fusion of methanol (CH 3OH) is 3.16 kJ/mol. How much heat would be absorbed or released upon freezing 25.6 grams of methanol. 1. 0.253 kJ absorbed 2. 2.52 kJ released 3. 3.95 kJ absorbed 4. 2.52 absorbed 5. 3.95 kJ released 6. 0.253 kJ released  

How much energy is required to vaporize 98.6 g of ethanol (C 2H5OH) at its boiling point, if its ΔH vap is 40.5 kJ/mol? A) 39.9 kJ B) 11.5 kJ C) 52.8 kJ  D) 86.7 kJ E) 18.9 kJ

The molar heat capacity of some molecule X(l) is 10 cal/K · mol, its heat of vaporization is 5000 cal/mol and its boiling point is 75◦C. For the conversion of one mol of X(g) at 75◦C to one mol of X(l) at 60◦C, 1. 5150 cal of heat are released by X.  2. 4850 cal of heat are released by X. 3. 150 cal of heat are released by X. 4. 4850 cal of heat are absorbed by X. 5. 5150 cal of heat are absorbed by X.

Ethanol (C2H5OH) melts at -114°C. The enthalpy of fusion is 5.02 kJ/mol. The specific heats of solid and liquid ethanol are 0.97 J/g•K and 2.3 J/g•K, respectively. How much heat (kJ) is needed to convert 25.0 g of solid ethanol at -135°C to liquid ethanol at -50°C? A) 207.3 kJB) -12.7 kJC) 6.91 kJD) 4192 kJE) 9.21 kJ  

What is the minimum mass of ice at 0 °C that must be added to the contents of a can of diet cola (340. mL) to cool the cola to 0 °C from room temperature (20.5 °C)? The heat of fusion for ice is 333 J/g. Assume the cola density is equivalent to water (1 g/mL).

The specific heat of liquid ethanol, C2H5OH(l), is 2.46 J/g•°C and the heat of vaporization is 39.3 kJ/mol. The boiling point of ethanol is 78.3°C. The molecular weight of ethanol 46 g/mol. What amount of enthalpy is required to heat 50.0 g of liquid ethanol from 23.0°C to ethanol vapor at 78.3°C?1) 42.7 kJ2) 49.5 kJ3) 179 kJ4) 1970 kJ5) 6840 kJ

You have a 100 g sample of water at standard pressure and 70 ◦C. How much energy is required to heat this sample to steam at 120◦C? A. 21 kJB. 239 kJC. 243 kJD. 17 kJE. 247 kJF. 185 kJ 

You have a sample containing 15 grams of solid ethanol together with 15 g of liquid ethanol. The sample is at the freezing temperature of ethanol, -114◦C. What happens when you initially place this mixture in a deep freezer which is held at -180◦C and energy flows out of the sample in the form of heat? A. The temperature of the sample decreases while the liquid ethanol freezes.B. The temperature of the sample remains constant while the liquid ethanol freezes.C. The temperature of the sample remains constant while the solid ethanol melts.D. The temperature of the sample increases while the liquid ethanol freezes.E. The temperature of the sample remains constant and the relative amount of liquid and solid ethanol remains constant.

Consider a 1 kg block of ice at standard pressure. If it is initially at −5°C and is heated until it is steam at 109°C, how much total heat was added to the sample of water? Use the following thermodynamic values for your calculation:cice = 2.09 J/g Kcwater = 4.184 J/g Kcsteam = 2.03 J/g K∆Hvap = 2260 J/g∆Hfus = 334 J/g1. 3950 kJ2. 2710 kJ3. 2620 kJ4. 3040 kJ5. 28.7 kJ

What is the enthalpy change associated with heating 20g of Al from room temperature (23°C) to its melting point at 660°C and then melting it. (Specific heat of Al, Cp = 0.900J/kg °C; ΔH fus = 437 kJ/mole)  

Use the information given below to calculate the energy involved in the conversion of 235 g of steam at 373 K to ice at 243 K. Be sure to use the correct sign and answer in kJ.Specific Heat, J/g.°C2.06 - ice4.18 - water2.03 - steamMolar heat of fusion for water, kJ/mol - 6.02Molar heat of vaporization for water, kJ/mol - 40.6

At 1 atm, how much energy is required to heat 75.0 g of H 2O(s) at –22.0 °C to H2O(g) at 145.0 °C? Helpful constants can be found below.

Four ice cubes at exactly 0°C with a total mass of 53.5 g are combined with 140 g of water at 85∘C in an insulated container. (ΔH°fus = 6.02 kJ/mol, water = 4.18J/g•°C) If no heat is lost to the surroundings, what is the final temperature of the mixture?

How much energy is required to heat 36.0 g H 2O from a liquid at 65°C to a gas at 115°C?  The following physical data may be useful.ΔHvap = 40.7 kJ/molCliq = 4.18 J/g°CCgas = 2.01 J/g°CCsol = 2.09 J/g°CTmelting = 0°CTboiling = 100°CA) 52.7 kJ      B) 91.7 kJ      C) 87.7 kJ      D) 63.5 kJ      E) 10.9 kJ

How much energy is released when 42.5 g of water freezes? 

Calculate the heat energy (kJ) released when 23.6 g of liquid mercury at 25.00°C is converted to solid mercury at its melting point.

Based on the thermodynamic properties provided for water, determine the energy change when the temperature of 0.850 kg of water decreased from 123°C to 19.0°C.

The specific heat of water is 1.00 cal/g C, the heat of vaporization of water is 540 cal/g, and the heat of fusion of water is 80 cal/g.  How much heat would be required to convert 10 grams of ice at 0 degrees C to 10 grams of water at 75 degrees C? 

After an afternoon party, a small cooler full of ice is dumped onto the hot ground and melts. If the cooler contained 5.60 kg of ice and the temperature of the ground was 43.0°C, calculate the energy that is required to melt all the ice at 0°C. The heat of fusion for water is 80.0 cal/g.

Assume that the values given here for 1 mole of methanol are constant over the relevant temperature ranges.Given the heating curve for 1 mole of methanol beginning at 170 K and ending at 350 K answer the following questions:What is the value of q gas for methanol?

The fluorocarbon compound C2Cl3F3 has a normal boiling point of 47.6 ºC. The specific heats of C2Cl3F3 (l) and C2Cl3F3(g) are 0.91 J/g.ºK and 0.67 J/g.ºK, respectively. The heat of vaporization for the compound is 27.49 kJ/mol. A. Calculate the heat required to convert 37.5 g of C 2Cl3F3 from a liquid at 12.75 ºC to a gas at 75.10 ºC. Express your answer using two significant figures. 

Ethanol (C2H5OH) melts at -114°C and boils at 78°C. The enthalpy of fusion of ethanol is 5.02 kJ/mol, and its enthalpy of vaporization is 38.56 kJ/mol. The specific heat of solid and liquid ethanol are 0.97 J/g•K and 2.3 J/g•K respectively. How much heat (kJ) is required to convert 24.0 g of ethanol at 21°C to the vapor phase at 78°C? Express your answer using two significant figures.