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Heating and Cooling Curves

Q. After performing some tests on an unknown material with constant mass, a lab student produces the given heat curve. Help this student label the key points of this graph. Answer bank: temp change 3, temp change 2, vaporization, temp change 1, time, temperature, no heat added, fusion

Solved • Apr 30, 2020

Heating and Cooling Curves

Q. Use the changes of state interactive to answer the question. Find the melting point and boiling point of each substance. melting point of water: _____ °C boiling point of water _____ °C melting point of bromine _____ °C boiling point of bromine _____ °C melting point of benzene _____ °C boiling point of benzene _____ °C

Solved • Apr 30, 2020

Heating and Cooling Curves

Q. An energy source emitted 183 Kcal of heat. A chunk of ice initially at a temperature of 0C was transformed into liquid water with a temperature of 25C. Water has the following thermodynamic properties: Hfusion = 6.02 KJ/mole, Cice = 2.10 J/gC, and Cwater = 4.18 J/gC. The amount of liquid water formed is approximately?

Solved • Apr 20, 2020

Heating and Cooling Curves

Q. What is the energy change when 76.9g of Br2 (g) condenses into a liquid at 59.5 degrees centigrade? Given: The delta H of vaporization of Br2 is 15.4kj/mol The normal boiling point of Bromine is 59.5 degrees centigrade.

Solved • Apr 16, 2020

Heating and Cooling Curves

Q. If 41.2 x103 J of energy is needed to raise the temperature of 170.0 g of a liquid from 18.8oC to 65.2oC, what is the specific heat capacity of the solution? A) 4.19 J/g•oC B) 5.22 J/g•oC C) 11.2 J/g•oC D) 12.0 J/g•oC

Solved • Apr 13, 2020

Heating and Cooling Curves

Q. The enthalpy change for converting 10.0g of ice at -25.0 C to water at 80.0 C is ____ kJ. The specific heats of ice, water and steam are 2.09 J/gK, 4.18 J/gk and 1.84 J/gK, respectively. For H2O, Hfus=6.01 kJ/mol and Hvap= 40.67 kJ/mol. a.) 7.21 b.) 6.16 c.) 3870 d.) 12.28 e.) 9.88

Solved • Apr 11, 2020

Heating and Cooling Curves

Q. How many grams of ice at -21.5 ∘C can be completely converted to liquid at 16.8∘C if the available heat for this process is 4.93×103 kJ? For ice, use a specific heat of 2.01 J/(g⋅∘C) and ΔHfus=6.01 kJ/mol

Solved • Apr 3, 2020