Algebra 1, High School Biology Recommended: The CLEP covers two years worth of material.
What is the percentage of sulfate in beryllium sulfate tetrahydrate? Notice that the examples here are done to two decimal points of the atomic weights. The problems in the practice bunch at the end of this chapter are done to one decimal point of the atomic weight.
Basic Stoichiometry Stoichiometry is a division of chemistry that involves proportions and relationships between reacting elements and compounds. Stoichiometry can take several forms. Three very common forms of stoichiometry are reaction stoichiometry, composition stoichiometry, and gas stoichiometry.
Pronounce stoichiometry as "stoy-kee-ah-met-tree," if you want to sound like you know what you are talking about, or "stoyk," if you want to sound like a real geek. Stoichiometry is just a five dollar idea dressed up in a fifty dollar name. You can compare the amounts of any materials in the same chemical equation using the formula weights and the coefficients of the materials in the equation.
The most common type of stoichiometry studied in introductory chemistry is reaction stoichiometry more commonly known as balancing equations. This type of stoichiometry involves finding coefficients of elements in chemical equations. This provides a way to quantify using a ratio the relationship between elements in a chemical reaction.
Most of the time, we assume that a chemical reaction goes to completion. This means that all the reactants are used up to make as much product as possible.
Sometimes, however, a reaction only happens part way; it doesn't go to completion.
In that case, you'll be given a percent yield, and will have to use that to figure out the ratio of elements that react. For most of our work here, we'll assume that the reactions go to completion. Balancing Equations There are a few rules for balancing equations.
First, the purpose of balancing an equation is to get the same ratio of all elements involved. This is in accordance witht the Law of Conservation of Energy, which says that matter energy is neither created nor destroyed.
Therefore, we'd have to have the same relative amounts in the reactants as we do the products. As mentioned before, this relies on correcting the ratios between elements.
Balancing equations is like balancing a scale-you have to have the same ratio on both sides of the yields arrow. Here is a basic skeleton to guide you in balancing equations. Balance any uncommon elements. Make sure that elements that you've already balanced are still balanced.
If not, you may have to go back and double the ratio you started with. Make sure that all elements are balanced. If they are, you're done. If they are not, identify which ones are out of balance, balance them, and then go back and check that O and H are balanced as well.
We'll give you a couple of examples of how to do this. Balancing a simple equation: We note that the ratio of oxygen is 2: Now, our equation looks like this: The coefficient of H2O means that there are not just 2 H2, but also 2 O. So, our ratio of oxygen is now 2: Next, we have to look at balancing hydrogen.
We look at our hydrogen ratio and see that it is 2: Now, there are two hydrogen molecules on the reactant side, and 4 on the product side.
In order to even this out, we would put a coefficient of 2 in front of the hydrogen on the reactant side, which means we'd be multiplying 2 times 2 in order to get 4 on the reactant side as well.
Now the equation is completely balanced.Worksheet Balancing Equations 1 Balance chemical equations Rob Writing Reactions Review 2 Solubility Rules Balancing Lab 10 reactions BetterLesson's unique formula allows us to bring you high-quality coaching, a professional learning lab, and a learn .
Please review the FAQs and contact us if you find a problem.. Credits: 1. Prerequisite: Algebra 1, High School Biology. Recommended: 11th. Test Prep: CLEP This course covers the basic material for a high school chemistry course.
The CLEP covers two years worth of material. Those wishing to take the CLEP will have to do significant additional .
Worksheet #1: Writing and Balancing Formula Equations Step 1: Write each formula and balance each formula using SUBSCRIPTS.
Step 2: Balance the overall equation using coefficients. Worksheet #1: Writing and Balancing Formula Equations. Step 1: Write each formula and balance each formula using SUBSCRIPTS Step 2: Balance the overall equation using coefficients.
Moles and Percents Why do we need Moles? A chemical mole, or mol, is a unit of measure, just like a gram or an ounce. It is used internationally so that all chemists speak the same measurement language.
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