85. The partial pressure of CH 4 (g) is 0.175 atm and that of 02(g) is 0.250 atm in a mixture of the two gases. a. What is the mole fraction of each gas in the mixture? b. If the mixture occupies a volume of 10.5 L at 65 D C, calcu-late the total number of moles of gas in the mixture. c. Calculate the number of grams of each gas in the mixture. 86. A 1.00-L gas sample at 100.DCand 600. torr contains 50.0% he-lium and 50.0% xenon by mass. What are the partial pressures of the individual gases? 87. Small quantities of hydrogen gas can be prepared in the labora-tory by the addition of aqueous hydrochloric acid to metallic zinc. Zn(s) + 2HCI(aq)----7 ZnCI 2 (aq) + HzCg) Typically, the hydrogen gas is bubbled through water for collec-tion and becomes saturated with water vapor. Suppose 240. mL of hydrogen gas is collected at 30. D C and has a total pressure of 1.032 atm by this process. What is the partial pressure of hydro-gen gas in the sample? How many grams of zinc must have re-acted to produce this quantity of hydrogen? (The vapor pressure of water is 32 torr at 30 D C.) 88. Helium is collected over water at 25 D C and 1.00 atm total pres-sure. What total volume of gas must be collected to obtain 0.586 g helium? (At 25 D C the vapor pressure of water is 23.8 torr.) 89. At elevated temperatures, sodium chlorate
This is the end of the preview. Sign up
access the rest of the document.
This note was uploaded on 12/13/2010 for the course CHEM 2301 taught by Professor Bill during the Spring '10 term at South Texas College.