MORE PHYSICAL STATES PROBLEMS!

  1. Sketch the triple point phase diagram of oxygen, O2, from the following information: normal melting point, -2180C; normal boiling point, -1830C; triple point, -2190C, 1.10 mm Hg; critical point, -1180C, 50.1 atm. Label each phase region on the graph.
  2. A tank of gas at 210C has a pressure of 1.0 atm. Using the following data, answer the following questions. Explain your answers.
  3. If the tank contains carbon tetrafluoride, could the liquid state be present?
  4. If the tank contains butane, could the liquid state be present?

SubstanceB.P. at 1 atm Critical Temp.Critical P.

CF4-1280C-460C41 atm

C4H10-0.50C1520C38 atm

  1. Shown here is the triple point phase diagram for compound Z. The triple point of Z is –5.10C at 3.3 atm and the critical point us 510C and 99.1 atm.

Pressure

(atm)

A

Temperature (0C)

  1. What is the state of Z at position A?
  2. If we increase the temperature from the compound at position A to 600C while holding the pressure constant, what is the state of Z?
  3. If we take the compound starting under the conditions of part b and reduce the temperature to 200C and increase the pressure to 65 atm, what is the state of Z?
  4. Would it be possible to make the compound starting under the conditions of part c a solid by decreasing just the temperature?
  1. Associate each of the solids: Co, LiCl, SiC, CHI3 with one of the following sets of properties:
  2. A white solid melting at 6130C; the liquid is electrically conducting, although the solid is not.
  3. A very hard, blackish solid subliming at 27000C.
  4. A yellow solid with a characteristic odor having a melting point of 1200C.
  5. A gray, lustrous solid melting at 14950C; both the solid and liquid are electrical conductors.
  1. Shown here is the triple point phase diagram for compound X. The triple point of X is –25.10C at 0.50 atm and the critical point is 220C and 21.3 atm.

Pressure

(atm)

A

Temperature (0C)

  1. What is the state of X at position A?
  2. If we decrease the temperature from the compound at position A to –28.20 while holding the pressure constant, what is the state of X?
  3. If we take the compound starting under the conditions of part b and increase the temperature to 15.30C and decrease the pressure to .002 atm, what is the state of X?
  4. Would it be possible to make the compound starting under the conditions of part c a solid by increasing just the pressure?
  1. Sketch the triple point phase diagram of argon, Ar, from the following information: normal melting point, -1890C; normal boiling point, -185.80C; triple point, -189.340C, .68 atm; critical point, -1220C, 48 atm. Label each phase region on the diagram.
  2. Sketch the triple point phase diagram of ammonia, from the following information: normal melting point, -77.70C; normal boiling point, -33.30C; triple point, -77.70C, .06 atm; critical point, 1320C, 111 atm. Label each phase region on the diagram.
  3. Sketch the triple point phase diagram of sulfur hexafluoride, from the following information: melting point, -510C at 2.2 atm; normal sublimation point, -63.70C; triple point, -50.520C, 1.8 atm; critical point, 45.50C, 37 atm. Label each phase region on the diagram.
  4. Sketch the triple point phase diagram of carbon monoxide, from the following information: normal melting point, -2070C; normal boiling point, -1920C; triple point, -2050C, .15 atm; critical point, -1400C, 34.5 atm. Label each phase region on the diagram.
  5. How many atoms are there in a body-centered cubic unit cell of an atomic crystal in which all atoms are at lattice points?
  6. How many atoms are there in a simple cubic unit cell of an atomic crystal in which all atoms are at lattice points?
  7. X-Ray diffraction from crystals provides one of the most accurate ways of determining Avogadro’s number. Silver crystallizes in a face-centered cubic lattice with all atoms at the lattice points. The length of an edge of the unit cell was determined by x-ray diffraction to be 408.6 pm. The density of silver is 10.50 g/cm3. Calculate the mass of a silver atom in grams using this experimental data of 408.6 pm. From this mass value, calculate Avagadro’s number.
  8. Lithium metal has a body-centered cubic structure with all atoms at the lattice points and a unit-cell length of 350.9 pm. Calculate the mass of a lithium atom in grams. The density of lithium is .534 g/cm3.
  9. Platinum crystallizes in a face-centered cubic lattice with all atoms at the lattice points. It has a density of 21.45 g/cm3 and an atomic weight of 195.08 amu. From these data, calculate the length of a unit cell edge in pm.
  10. Potassium metal has a body-centered cubic structure with all atoms at the lattice points. It has an atomic mass of 39.1 amu. The density of the metal is .856 g/cm3. Calculate the edge length of a unit cell.
  11. Nickel has a face-centered unit cell with all atoms at lattice points and an edge length of 352.4 pm. The density of nickel is 8.91 g/cm3. What is the mass of a nickel atom in grams? You must use the 352.4 pm measurement in your calculations!
  12. Lead has a face-centered cubic lattice with all of its points at lattice points and a unit-cell edge length of 495.0 pm. Its atomic weight is 207.2 amu. What is the density of lead, using these values?
  13. Chromium forms cubic crystals whose unit cell has an edge length of 288.5 pm. The density of the metal is 7.20 g/cm3. Using this data, what is the number of atoms in a unit cell of chromium? What type of cubic lattice does chromium have?
  14. Metallic magnesium has a hexagonal close-packed structure and a density of 1.74 g/cm3. Because magnesium has a close-packed structure, 74.1% of the space is occupied by atoms. Calculate the volume of each atom; then, find the atomic radius, r, in pm.
  15. Metallic silver has a cubic close-packed structure. This packing efficiency allows silver to be an incredible conductor of both heat and electricity. Calculate the volume of a single silver atom; then, find its atomic radius, r, in pm.
  16. Copper metal has a face-centered cubic structure, with all atoms at lattice points and a density of 8.93 g/cm3. Its atomic weight is 63.5 amu. Calculate the edge length of the unit cell.
  17. Gold has cubic crystals whose unit cell has an edge length of 407.9 pm. The density of the metal is 19.3 g/cm3. From these data and the atomic weight, calculate the number of gold atoms in a unit cell, assuming all atoms is at lattice points. What type of cubic lattice does gold have?
  18. Tungsten has a body-centered cubic lattice with all atoms at lattice points. The edge length of the unit cell is 316.5 pm. The atomic weight of tungsten is 183.8 amu. Calculate its density.
  19. Aluminum metal, prized for its lightness and strength, forms cubic crystals. One unit cell has a unit length of 405 pm. Calculate the number of atoms in a unit cell of aluminum. What type of crystal lattice does aluminum form, based on your calculations?
  20. Classify each of the following solids as molecular, metallic, ionic, or covalent network. Explain your answer.
  21. A lustrous, yellow solid that conducts electricity
  22. A hard, black solid melting at 23500C to give a non-conducting liquid
  23. A non-conducting, pink solid melting at 6500C to give an electrically conducting liquid
  24. Red crystals having a characteristic odor and melting at 1710C