Chem 6B Crowell Practice Exam 2

Chem 6B Crowell Practice Exam 2 - CHEM 6B PRACTICE EXAM 2A...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Chem 6B Practice Exam 2A 1 - A Prof. Crowell CHEM 6B PRACTICE EXAM 2A (Prof. Crowell) Wtr 2008 Feb. 8, 2008 *** FILL IN YOUR STUDENT ID NUMBER , NAME , and TEST FORM = A *** Bubble in the correct response on scantron (26 questions, worth 4 pts each) 1. The phase diagram for CO 2 is given below. The triple point is at 5.1 atm and 217 K. What happens if carbon dioxide at 50 ° C and 35 atm is suddenly brought to 1 atm? a). The liquid and solid are in equilibrium. b). The solid vaporizes. c). The solid melts. d). The solid and vapor are in equilibrium. e). The solid remains stable. 2. Hydrogen peroxide (H 2 O 2 ) is a powerful oxidizing agent used in concentrated solution in rocket fuels and in dilute solution as a hair bleach. An aqueous solution of H 2 O 2 is 30.0 % by mass and has a density of 1.11 g/mL. Calculate its molarity (in mol/L). a). 0.013 b). 9.79 c). 8.8 d). 12.6 e). 300 3. The vapor pressure of methanol at 25 ° C is 123 Torr and its enthalpy of vaporization is 35.3 kJ mol 1 . Estimate the normal boiling point of methanol. Assume the enthalpy of vaporization is independent of temperature. a). 450 K b). 373 K c). 342 K d). 315 K e). Not enough information given 4. Calculate the concentration of argon in lake water at 20 ° C. The partial pressure of argon is 6.84 torr and Henry's constant is 0.0015 mol L 1 atm 1 . a). 1.0 × 10 2 M b). 6.0 M c). 9.0 × 10 3 M d). 0.17 M e). 1.4 × 10 5 M 5. Calculate the total vapor pressure at 25 ° C of a mixture of benzene and toluene in which the mole fraction of benzene is 0.650. The vapor pressure at 25 ° C of benzene is 94.6 Torr and that of toluene is 29.1 Torr. a) 84.4 Torr b) 124 Torr c) 51.3 Torr d) 71.7 Torr e) 61.5 Torr
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Chem 6B Practice Exam 2A 2 - A Prof. Crowell 6. For CaCl 2 , the absolute value of the enthalpy of hydration is larger than the absolute value of the lattice enthalpy. This means that for CaCl 2 a). the lattice enthalpy is negative. b). the enthalpy of solution is endothermic. c). the enthalpy of solution is exothermic. d). the enthalpy of hydration is positive. e).
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 4

Chem 6B Crowell Practice Exam 2 - CHEM 6B PRACTICE EXAM 2A...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online