Question

TIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Which of the following processes is exothermic? 1) A) The chemical reaction in a "cold pack" often used to treat injuries B) The melting of ice. C) The formation of dew in the morning D) The vaporization of water E) None of the above are exothermic 2) If a sample of 0.29 moles of Ar occupies 3.8 L under certain conditions, what volume will 0.66 2) moles occupy under the same conditions? A) 8.6 L B) 12L C) 17L D) 5.0 L E) 15 L 3) A mixture of He, Ne and Ar has a pressure of 7.85 atm. If the Ne has a mole fraction of 0.47 and Ar 3) C) 4.2 atm has a mole fraction of 0.23, what is the pressure of He? A) 1.8 atm B) 2.4 atm D) 3.7 atm E) 5.5 atm 4) Which of the gases in the graph below has the largest molar mass? 4) 1000 1500 2000 2500 Molecular Spod A) A ?) ? C) C D) D E) There is not enough information to determine. 5) 5) Which of the following will cause the volume of an ideal gas to triple in value? A) Lowering the absolute temperature by a factor of 3 at constant pressure. B) Lowering the absolute temperature by a factor of 3 while increasing the pressure by a factor of 3. C) Lowering the pressure by a factor of 3 while the temperature stays constant. D) Raising the absolute temperature by a factor of 3 while increasing the pressure by a factor of 3. E) Raising the temperature from 25°C to 75 C at constant pressure.

Answer 1