# Boyle’s Law: History and Work Problem

The two variables we're looking at today are pressure and volume, whose gas relationship was discovered during the Renaissance.

# Work Problem: Light and Photons

What we often refer to as 'light' is a narrow portion of a broad spectrum of electromagnetic radiation. This spectrum stretches from radio waves with a wavelength of 10³ m to gamma rays with a wavelength of 10⁻¹² m. We work mainly with light in the visible spectrum in this lesson, but the fundamentals learned here can be applied to any portion of the EM spectrum.

# Profile: Iréne Joliot-Curie

Iréne Curie was born on September 12, 1897 in Paris, France to Marie and Pierre Curie. She was the oldest of two, her younger sister Eve being born in 1904. Iréne grew up to be a bright, smart, and quick young woman. Marie and Pierre would be awarded the 1903 Nobel prize in physics alongside Henri … Continue reading Profile: Iréne Joliot-Curie

# Interview with James Nowick- Researcher, Educator, Advocate (A Profile Piece)

HeychemTutor got a chance to sit down with esteemed professor and advocate Dr. James Nowick, who is currently based out of the University of California-Irvine. We sat down to discuss chemistry, LGBTQIA+ rights, and advocacy. This was a project Heychem set in celebration of June 2017 Pride month. ~~Interview Start~~ HeyChem: How did you first … Continue reading Interview with James Nowick- Researcher, Educator, Advocate (A Profile Piece)

# 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 … Continue reading Determining the Molar Solubility of Iron (II) Hydroxide

# 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 … Continue reading Calculating the pH of a Buffer System

# Titration of Strong Acid With Strong Base

The goal of this example is to help students become fluent in calculating pH/pOH of a solution during a titration of a strong acid (HCl) and a strong base (NaOH). This problem includes calculations for titrations of increasing volumes. Given Problem: Calculate the pH of a titration of 25.0 mL of HCl (.100 M) with … Continue reading Titration of Strong Acid With Strong Base

# Profile: Amedeo Avogadro

Lorenzo Romano Amedeo Carlo Avogadro, conte di Quaregna e Cerreto or as we know him, Amedeo Avogadro, was born on August 9th, 1776 in Turin, Italy. His father, a lawyer turned senator in Italy, Avogadro began his education in the pursuit of law. Avogadro earned his law degree in 1792, but did not start practicing … Continue reading Profile: Amedeo Avogadro

# VSEPR Theory Examples (chem.purdue)

Given Problem: Draw the Lewis dot structures, identify the molecular geometry, and give the bond angle for the following compounds: BeF2 BCl3 SI6 1. BeF2: The first step is to draw the Lewis dot structure. This can be done by identifying how many bonding groups are involved.  A bonding group, counts as 1 lone electron, an electron pair, … Continue reading VSEPR Theory Examples (chem.purdue)

# Determining the Density of a Face-Centered Aluminum Cell

Crystals come in unique shapes, but all usually have an organized, repeating structure known as a lattice. For more information about metal lattices check out: https://www.seas.upenn.edu/~chem101/sschem/metallicsolids.html  Given Problem: An aluminum crystal has a face-centered unit cell. An aluminum atom has a radius of 143 picometers. What is the density of the solid crystal aluminum in g/cm³?  … Continue reading Determining the Density of a Face-Centered Aluminum Cell