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Hello.
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Today we'll talk a little bit about chapter 12, question 68, which tells us about the lithium hydroxide -based co2 scrubber used in spaceships.
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And so, if we think about a spaceship that is a partial pressure of co2 of 5 .0 kilopascals, we have a large spaceship that has a volume of 8 times 10 to the 4th liters.
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Maybe we have a room in a spaceship, and we have a temperature of 15 degrees celsius.
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We keep it nice and air -conditioned.
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We'll write our gas constant, which we can look up in a table of 8 .314 liters kpa per mole kelvin.
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And so all we don't have is n in relation to our ideal gas law, pv equals nrt.
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And so we're asked to determine how much lithium hydroxide is needed to react with the co2 described by these conditions.
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And so if we write out our gas law to solve for n, so we have the pressure, volume, the gas constant, and the temperature, so long as we convert it to kelvin by adding 273, 288 kelvin, we have our temperature, and we can solve for n, the number of moles.
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Of co2.
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So n equals pv over rt and if we plug some numbers in we get n is equal to 5 .0 kpa times 8 times 10 to the 4th liters divided by r the gas constant which i'm abbreviating and 288 kelvin and this gives us a number of moles of co2 gives so 167 .167 .1 moles of co2...