Episode 4: Reactions

I realize I didn’t post this earlier! My bad on that. Questions? Comments? Concerns? Drop us a line at heychemblog@gmail.com. We’d love to hear from you. Video troubles? You can find us on Youtube as well.

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Episode 5b: Combustion Reactions

Episode 5B: Combustion Reactions   This episode is on FIRE! All about combustion reactions and the information we can gain from them. Misspeak at ~5:57, should be grams hydrogen. Music: Good For You by THBD https://soundcloud.com/thbdsultan Creative Commons — Attribution 3.0 Unported— CC BY 3.0 http://creativecommons.org/licenses/b… Music provided by Audio Library https://youtu.be/-K_YSjqKgvQ Find us at […]

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Determining the Molar Solubility of Iron (II) Hydroxide

Given Question: Calculate the molar solubility of Fe(OH)2 (Ksp=4.87*10^-7).  Tutor’s Note: The Ksp radical that’s written down comes in later, I got confuzzled by my own notes! Happens to all of us. Sorry students 🙂  Step 1: Write out the reaction equation with all ions. Make sure it’s balanced! We’ll use this in the next step with […]

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Profile: Ruby S. Hirose

Ruby S. Hirose- an unsung northwest powerhouse who contributed to the polio vaccine among many other accomplishments.

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Profiles: George Washington Carver

George Washington Carver was born in Diamond, MO, in 1864/5, though the real date is unknown. Born into slavery, Carver’s parents Giles and Mary were owned by a German immigrant slaveholder Moses Carver. At the conclusion of the civil war, Moses Carver and his wife Susan decided to keep George and his brother James. Susan […]

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Calculating the pH of a Buffer System

The point of this problem is to correctly calculate the pH of a buffer system using formonitrile, or hydrogen cyanide. Here, we use the dissociation constant and the Henderson-Hasselbach equation. Given Problem: Calculate the pH of a buffer that’s .250 M HCN (kª= 4.9*10^-10) and 0.170 M KCN.  2. This is to remind us of the […]

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Calculating Percent Yield

Given Questions: 155.8 Kg of SiO2 reacts with 78.3 Kg of Carbon to produce 66.1 Kg of silicon. What is the percent yield of the reaction? 1. The first step is to convert your given masses into moles. This way, you can see which reactant is in excess and which one is limiting. A good […]

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Percent Mass Composition Example

The point of these problems is to calculate the mass of a specific element in a given compound. We’re given 88.07 grams of C4H8S, and the molar mass of sulfur is 32.07 grams/mol. We know that the % mass composition is found by dividing the molar mass of our target element by the total mass […]

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