Here is the problem summarized according the stoichiometry strategy: Quantity A mol A mol B Quantity B → → → P, V. T of CO2 mol CO2 mol CaCO3 g CaCO3 to %CaCO3 → → → In the last step, we divided the grams of CaCO3 by the grams of antacid table and multiplied by 100 to obtain a percent. A percent is the quantity of a divided by a multiplied by 100. See how “part” “whole” the units in the above expression relate this! 16. What is the density of sulfur dioxide gas at 974 torr and a temperature of 55.7 °C? From the ideal gas law we can derive an expression that relates, molar mass, pressure, density and temperature. Start with PV = nRT. The moles, n, can be substituted with mass in grams (g) divided by molar mass, : Multiply through by mass: Divide by volume, V: Since density, D, is mass divided by volume (g/V), substitute D for g/V: An easy way to remember this equation is the mnemonic Pies are made from DiRT”. “Mud 16 (continued) Using this equation, collect your terms and convert them to the appropriate unit: = 64.07 g/mol D = ? g/L R = 0.08206 L∙atm/mol∙K T = 55.7 °C + 273.15 = 328.8 K Rearrange and solve for density:
Here is the problem summarized according the stoichiometry strategy: Quantity A → mol A → mol B → Quantity B P, V. T of CO2 → mol CO2 → mol CaCO3 → g CaCO3 to %CaCO3 In the last step, we divided the grams of CaCO3 by the grams of antacid table and multiplied by 100 to obtain a percent. A percent is the quantity of a “part” divided by a “whole” multiplied by 100. See how the units in the above expression relate this! 16. What is the density of sulfur dioxide gas at 974 torr and a temperature of 55.7 °C? From the ideal gas law we can derive an expression that relates, molar mass, pressure, density and temperature. Start with PV = nRT. The moles, n, can be substituted with mass in grams (g) divided by molar mass, : Multiply through by mass: Divide by volume, V: Since density, D, is mass divided by volume (g/V), substitute D for g/V: An easy way to remember this equation is the mnemonic “Mud Pies are made from DiRT”. 16 (continued) Using this equation, collect your terms and convert them to the appropriate unit: = 64.07 g/mol D = ? g/L R = 0.08206 L∙atm/mol∙K T = 55.7 °C + 273.15 = 328.8 K Rearrange and solve for density:
akgaslaws.docx