C.Fuller+and+T.Patton+Example+Problems

In order to convert a given amount of gas to a different unit you must first note what the given and desired units are. In this example, i will solve a problem starting in Killograms and ending in milliliters. The second example will demonstrate a conversion form milliliters to killograms.

Problem #1: Convert 50kg of O2 (Oxygen gas) to volume in milliliters. Given: 50 Kg of O2 Steps: Kg to g, g to moles, moles to liters, liters to milliliters.

Step 1: Kg to g The first step to succesfuly converting a mass to a volume is to convert the mass to the right unit of mass. In this case we are in Kg, but in order to do the rest of the conversion we need to be in g. To do this, we mutliply the 50kg by 1000g/1kg, because the ratio of grams to killograms is 1000 to 1. By multiplying by this ratio we are replacing Kg with g. 50Kg O2X1000g/1Kg=50,000g of O2

Step 2:g to moles The next step is converting the 50,000g of O2 into a number of moles of O2. This step requires that you know the molecular mass of the gass you are working with, in this case it's 32 Amu. Because we want the mass of one mol of O2 32 AMU is regarded as 32g because one mol of a material gives you the mass equal to the number value of its atomic mass except in grams. This means that the ratio of moles to grams in O2 is 1 mol to 32 grams. this ratio is multiplied with the number of grams to convert it to a number of moles. 50,000g of O2X1mole/32g=1562.5mol O2

Step 3:Moles to liters For this step calculations are done assuming that the gas is under ideal conditions, so it uses a simple constant ratio of 22.4 liters per mole of the gas. This ratio cancels out the moles and replaces it with liters 1562.5mol O2X22.4/1mol=35,000L O2

Step 4:Liters to milliliters This last step uses a simple conversion ratio to turn liters into milliliters. It works based on th fact that there are 1000 milliliters in 1 liter. 35,000L O2X1000mL/1L=35,000,000mL O2

FINAL ANSWER: 35,000,000mL of O2

Problem #2: Convert 100mL of O2 into Kg Given:10,000mL of O2 Steps:mL to L, L to mol, mol to gram, gram to Kg

Step 1:mL to L Doing this conversion is no harder when you start with mL than when you start with Kg. For the most part you just do the setup backwards and reverse the ratios. This first step convert mL to L using the conversion ration of 1000mL to 1L. 10,000mL of O2X1L/1000mL=10L of O2

Step 2:L to mol This step uses that ratio I mentioned before that deals with the volume of 1 mol of gas under the ideal conditions. That ratio was 22.4L per mol or 1 mol per 22.4L. 10L of O2X1mol/22.4L=0.45mol O2

Step 3:mol to g Just like when we converted from g to mol in the last problem we need to know the molecular mass of 1 mol of the gas. In our case, because we are still using O2 the molecular mass is still 32g. The only difference is that the ratio is fliped to get us out of moles and into g. 0.45mol O2X32g/1mol=14.4g O2

Step 4:g to Kg The ratio of grams to killograms as we discused is 1000g to 1Kg. This means that the ratio that will be mutiplied by will be 1Kg/1000g. This step is simply to convert from grams to killograms. 14.4g O2X1Kg/1000g=0.0144Kg O2

FINAL ANSWER: 0.0144Kg O2

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