A 1.20-g sample of dry ice is added to a 755 mL flask containing nitrogen gas at a temperature of 25.0 °C and a pressure of 725 mmHg. The dry ice sublimes (converts from solid to gas), and the mixture returns to 25.0 °C. What is the total pressure in the flask?

Video transcript

Hey everyone. So here we have a 350 millim flies. It contains helium gas at 345 mm from Crete And 53°C We have a 6.72 g sample of ethylene added to the flask and evaporates into a gas. Whereas calculate the total pressure in the flask. So Nasa lean equal C. 10 H eight. We need to use the ideal gas law to find the pressure of Naphthalene 1st. And this is P. V. It was N. R. T. And we can rearrange this is all for the pressure. We're gonna get pressure because malls are constant times temperature by by volume over the pressure. This is what we're looking for. Volume 350 male leaders. We also need to find a number of moles For our constant have 0.08 21 Later sounds atmosphere. What about malls kelvin? The temperature we have 53 degree Celsius. Since we don't have moles, we need to convert the massive naphthalene into moles. Were given 6.72 grams of Magdalene. In one ball of naphthalene. We have the miller mass. We have 10 carbon And the massive carbon is 12.011 g. We have eight hydrogen. The mass hydrogen is 1.008. This give us 128. 17 g. They're gonna get 0.052. Malls of C 10 H eight. Since the volume is in male leaders. We need to convert to leaders. We have 350 male leaders. And in 1000 Male leaders have one leader. Let's give us 0.3 50 liters. And now we need to convert our temperature into kelvin 53 Grace Celsius. We need to add 273.15. Give us 326 15 kelvin. So now we can plug the values into the equation. We're going to get pressure Equal to 0. models From 0.08 206. Later some atmosphere barbara malls, kelvin, Some 326 15 kelvin By 0.35 Leaders Just give us four atmosphere The pressure of Madeline. And now we need to cover up the pressure from atmosphere millimeters of mercury. We have four atmosphere and in one atmosphere 760 millimeters of mercury. This give us 3040 mercury. Now to solve for the total pressure, we're gonna have a partial pressure of helium plus the partial pressure of nafta lean total pressure. We're gonna get 345 millimeters of mercury Plus 3040 millimeters of mercury. For the total pressure. We're gonna get 3385 millimeters of mercury. Thanks for watching my video and I hope it was helpful