S2 W15 HW

If 8.00 kJ of heat are added to 200. g of water at 20.0 °C, what is the final temperature of the water?

• 29.6°C

• 41.5°C

• 23.3°C

• 81.7°C

• 9.6°C

Tags

NGSS.HS-PS3-4

The specific heat for liquid argon Ar(l) is 25.0 J/mol·°C and gaseous Ar(g) is 20.8 J/mol·°C. The enthalpy of vaporization is 6506 J/mol. How much energy is required to convert 1 mole of liquid Ar from 5°C below its boiling point to 1 mole of gaseous Ar 5°C above its boiling point?

• 6960 J

• 6735 J

• 6555 J

• 6495 J

• 6290 J

Tags

NGSS.HS-PS3-4

The heat of vaporization is

• the amount of energy needed to transform a given quantity of a liquid at the boiling point to vapor at the same temperature.

• the amount of energy needed to cause a thermonuclear reaction.

• the amount of energy needed to transform a given quantity of a solid at the melting point to a liquid at the same temperature.

• the heat liberated per given quantity of solid upon heating.

Tags

NGSS.HS-PS3-4

The heating curve below represents the uniform heating of substance X starting as a solid below its melting point and ending as a gas. Identify the process that takes place during line segment DE of the heating curve.

• vaporization

• melting

• freezing

• sublimation

• deposition

Tags

NGSS.HS-PS3-2

NGSS.HS-PS3-4

Which of the following statements is NOT true?

• During line segment BC, the kinetic energy is increasing

• At point B,substance X begins to melt

• Between points C and D the substance exists as a liquid

• The amount of energy required to melt substance X is less then the amount of energy required to vaporize substance X

Tags

NGSS.HS-PS3-1

NGSS.HS-PS3-4

All of the processes listed below are cooling processes, in which the system undergoing the process absorbs heat from the surrounding environment, except for one. Which one is not a cooling process?

• Sublimation of solid to vapor.

• Evaporation of liquid to vapor.

• Melting of solid to liquid.

• Expansion of a gas.

• Freezing of liquid to solid.

Tags

NGSS.HS-PS3-4

Edgar is curious to discover the heat required to completely melt a 6.2g sample of ice that is initially stored at -78.5°C. Is this heat released or absorbed by the sample?

• 0 kJ of heat is released

• 3.1 kJ of heat is absorbed

• 28 kJ of heat is absorbed

• 3.1 kJ of heat is released

• 2.0 kJ of heat is released

How much heat is released when 10 g of steam at 115°C is cooled to ice at –15°C? Use the approximate values c_ice = 2 J/g·°C, ΔH_vap = 2260 J/g, c_steam = 2 J/g·°C, c_water = 4 J/g·°C, ΔH_fus = 340 J/g for your calculation.

• –26600 J

• –8000 J

• –30600 J

• –30300 J

• –30000 J

Tags

NGSS.HS-PS3-1

NGSS.HS-PS3-4

10 g of water at 25°C is cooled to ice at –50°C. What is overall ΔH_sys for this process?

• -6.02 kJ

• -3.34 kJ

• -5.4 kJ

• -7.02 kJ

Tags

NGSS.HS-PS3-4

A coffee cup calorimeter contains 150g of water at 24.6°C. A 110g block of metal at 30.0°C is then placed in the calorimeter. The contents of the calorimeter come to 28.0°C. What is the heat capacity of the metal?

• 9.68 J/g°C

• 0.269 J/g°C

• 2130 J/g°C

• 5.20 J/g°C

Tags

NGSS.HS-PS3-4