Before class on Sept. 2,
- Watch the video below (13 min) on empirical and molecular formulas;
- Take notes using the note sheet (if you don’t have it from class, click here: NOTES Lesson 2 Empirical Formula)
- When done, write a comment on the video summarizing something you learned, or asking a question. If you are doing this on a phone, click on the post, and at the bottom write your comment where it says “leave a reply”
https://www.youtube.com/watch?v=kBaZos9PAuU
chemistry matters 
Empirical is a chemical formula that shows the simplest ratio in a compound or the lowest common denominator. First step to figure out the empirical formula when given a mass percent is to assume that you have 100g of the substance. You can find out the molecular formula by diving the molar mass with the empirical formula mass.
Question: none
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Empirical formula is the formula of a compound with the lowest possible subscripts.
Is the empirical formula or the molecular formula used in stoichiometry?
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I learned how to determine the empirical and molecular formulas of a compound.
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You can find the empirical formula (and eventually molecular formula) given mass percents using proportions. If you assume that you have 100 grams of a substance, then you can set up a proportion with the molar mass/one mole and mass percent x 100 grams/x moles to find the number of moles. Once you have the number of moles of each elements, you can compare the numbers to each other in proportions to figure out what the subscripts are for the empirical formula. Once you have the empirical formula, you can figure out what coefficient to multiply all the subscripts by to get to the molecular formula with a proportion again (as long as you are given the molar mass of what you are trying to find). To do this, you would need to divide the molar mass by the empirical mass to see how many times larger the molar mass is. Then you would multiply all the subscripts in the empirical formula by the quotient of molar mass and empirical mass to find the molecular formula.
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The empirical formula is the simplest form of the molecular formula.
To find the empirical formula, you must find the lowest common denominator of the subscripts in the molecular formula and use that as the subscripts instead.
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You can figure out a compound’s empirical formula by 1) figure out how much you have assuming you have 100g 2) convert the grams to moles and 3) calculating proportions of moles to each other
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The empirical formula is a formula the shows the simplest ratio of elements in a compound but not the actual numbers or arrangement of atoms ( which is molecular formula). In order to find the empirical formula when given mass percent information, the first step would be figuring out how much of each element you have assuming you have 100g of the substance. Next, you convert the mass to mole. Lastly, you need to find the proportions of moles of each elements to each other. Those ratios will be the empirical formula subscripts.
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Empirical formula is the basic formula and molecular formula is how the molecules are bonded to each other. we also learned how to figure out empirical and molecular formula when the mass percent and mollar mass are given.
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The empirical formula has the lowest common denominator for that formula.
To find the empirical formula, assume it is a 100 g sample and replace % with g; then use the atomic masses to convert from grams to moles; after that, find the mole ratio by dividing by the smallest number (mole); and finally, write the formula using numbers as a subscript.
To find the molecular formula, divide the molar mass of the molecular formula by the molar mass of the empirical formula; then rewrite the formula as a multiple of the empirical formula.
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Basically, today we learned how to to get the empirical formula and molecular formula of a compound when given mass percentages assuming you have 100g of the substance. Empirical is the most simplified version of the compound, whereas molecular is the less simplified version.
What significance in chemistry do empirical and molecular formulas play? Are they more than just compounds with different subscripts?
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The empirical formula is the molecular formula in its simplest form. We can use the lowest common denominator strategy to figure the empirical formula out. To figure out the empirical formula when given mass percent, you first assume that you have 100g of the substance. Then figure out how much of each you have, convert to moles, and figure out the proportions of moles to each other.
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Empirical is a simplified version of the equation, where molecular is less simplified.
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