slevey,+dalton's+law+of+partial+pressure.

dalton's law of partial pressure.
john dalton discovered the dalton's law of partial pressure. partial pressure is the pressure of each gas in a mixture. dalton's law of partial pressure states that the total pressure of a gas mixture is the sum of the partial pressures of the component gases.

//this is how the law is expressed:// Ptotal = P1 + P2 + P3...etc.

this law can also be expressed this way: Patm = Pgas + PH2O.

oxygen gas from the decomposition of potassium chlorate, KClO3, was collected by water displacement. the barometric pressure and the temperature during the experiment were 731 torr and 20° celcius, respectively. what was the partial pressure of the oxygen collected?
 * here is a practice problem:**

//converting celcius to kelvin:// remember that in chemistry, we use kelvin in problems, not celcius! add 273 to every celcius temperature. 20° celcius + 273 = 293 K.

//fill in your variables:// Patm = 731 torr. PH2O = 17.5 torr (vapor pressure of water at 20° celcius.) PO2 in torr = unknown.

//rearranging the equation to find the unknown:// we don't do a lot of rearranging here, but we will change the original Pgas, to PO2.

//fill in the correct values for the variables:// PO2 = 731 torr - 17.5 torr = 713.5 torr.

[problem from page 367 in the chemistry textbook.]

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