In class, we learned about empirical formulas and molecular formulas. These two different types of formulas have different characteristics; however, they sometimes are the same. An empirical formula is the lowest number ratio of elements in a compound- it can't be reduced. Molecular formulas are the ratio of masses in whole numbers of the empirical formula. Since molecular formulas are ratios of masses and whole numbers, they can be the same as its empirical formula. In order to calculate An empirical formula, you take the mass percentage of the element and change it to grams. Next, divide the grams of each element by the molar mass, found on the periodic table. After having calculated the moles, the mole ratio is calculated and put into the lowest mole number. The answer can either end with a whole number or a decimal that can be multiplied by a whole number into a whole number.
http://quantummechanics.mchmultimedia.com/2011/general-chemistry-general-chemistry/004-empirical-formula-in-chemistry/
http://slideplayer.com/slide/235679/
Some links I found helpful in working on empirical and molecular formulas:
Empirical Formula
Molecular and Empirical Formulas
Formula Practice
Thanks, Erin, this was a fantastic post! I wish I had read this before our quiz because you so clearly and thoroughly explained this topic! You did a great job stating the differences and the steps on how to convert from one to another. Your pictures and links were also of great assistance for understanding and applying with practice. I will be sure to check out your blog more for information like this, especially when I am confused. Keep up the good work!
ReplyDeleteThis was a very helpful post that gave me a better understanding of empirical and molecular formulas, especially the pictures and links. I used this post as part of studying for the exam.
ReplyDeleteI wish I would've seen this before the test! I love the pictures and links that you shared. These could've been very useful for studying and formula practice. Thanks for posting!
ReplyDelete