Ethylene glycol, C2H6O2, is a colorless liquid used as auto-mobil...

Question

Ethylene glycol, C2H6O2, is a colorless liquid used as auto-mobile antifreeze. If the density at 20 °C of a 4.028 m solu- tion of ethylene glycol in water is 1.0241 g/mL, what is the molarity of the solution? The molar mass of ethylene glycol is 62.07 g/mol

Accepted Answer

Hey everyone, we're told that sodium hypochlorite is the component of household bleach. A 5.38 to morality solution of sodium hypochlorite in water has a density of 1.24 g per milliliter at 20 degrees Celsius expressed the concentration of sodium hypochlorite as more clarity as we've learned morality, which is signified by our little M. Is going to be our moles of solute divided by our kilograms of solvent. Now in comparison to our polarity, which is symbolized by our capital M. This is going to be our moles of solute divided by our leaders of solution. As we can see from our questions stem, we have a 5.38 to morality of sodium hypochlorite. This means that we have 5.382 mole of sodium hypochlorite divided by one kg of water first. Let's go ahead and calculate the mass of our solution and to do so, we're going to use dimensional analysis. Starting off with our 5.382 mole of sodium hypochlorite. We're going to use sodium hypochlorite, smaller mass and we know that we have 74.44 g of sodium hypochlorite per one mole of sodium hypochlorite. When we calculate this out, we end up with 400. grams of sodium hypochlorite. Now to get the total mass of our solution, All we need to do is take that value of 400. grams and add that one kg of water. But since we are in grams, we need to convert those kilograms into grams. So we have one kg of water and we know that per one kg we have 10 to the 3rd g. So when we calculate this out, we end up with a total of 1,400. g of solution. Now let's go ahead and calculate the volume of our solution. So we're going to take that value of 1,400. g of our solution. Now using the density they provided us, we're going to use our dimensional analysis and we know that per one mL of solution, We have 1.24 g of solution. And since we do want our polarity in leaders, we're going to convert our milliliters into leaders. Now we know that we have 10 to the 3rd ml per one leader. So when we calculate this out and cancel out all of our units, we end up with a volume of 1. L. Now let's go ahead and calculate our polarity. And as we said in the beginning, Polarity is going to be our moles of solute which is 5. mole of sodium hypochlorite. And we're going to divide this by our leaders of solution which we calculated to be 1.1295 leaders. So when we calculate this out, we end up with the polarity of 4.765 molar which is going to be our final answer. Now, I hope that made sense and let us know if you have any questions.

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