Unit 1 (The Basics)

This video introduces the scientific method as the foundation for scientific inquiry and experimentation. It walks students through the steps: making observations, forming questions, hypothesizing, conducting experiments with independent and dependent variables, analyzing results, and drawing conclusions. Greg uses a relatable example involving dissolving sugar in tea to demonstrate how the method works in practice and highlights the importance of controls, experimental groups, and peer review in maintaining scientific integrity.

This lesson dives into the concept of significant figures and why they matter in scientific measurement and calculations. Through relatable examples, Greg explains how different numbers of digits communicate different levels of precision and how to count significant figures correctly. The video also covers how to round answers appropriately in mathematical operations, distinguishing between rules for multiplication/division and addition/subtraction. Practice problems and free resources accompany the video for reinforcement.

Greg teaches students how to express very large or small numbers in scientific notation, making it easier to work with measurements in chemistry. The video explains the format of scientific notation, how to convert between standard and scientific form, and how to maintain significant figures during conversions. It also demonstrates how to use scientific notation in operations like multiplication, division, addition, and subtraction—both manually and with a calculator—along with several practice problems and helpful worksheets.

This lesson explains how scientific measurements are made using the metric system, which is based on base units and prefixes. Greg contrasts the metric and imperial systems and demonstrates how to convert between units using the reference table. Students learn how prefixes like kilo-, milli-, micro-, and nano- modify base units and how to perform conversions efficiently. The video emphasizes the importance of mastering these skills early and provides digital worksheets and answer keys for practice.

This video teaches students how to convert complex units using dimensional analysis, a method that ensures accuracy by canceling out units through fraction multiplication. Greg demonstrates how to convert meters per second to kilometers per hour by using conversion factors in stepwise fashion, reinforcing the logic of canceling units across numerators and denominators. The lesson simplifies a potentially tricky topic and helps students build a strong foundation for multistep unit conversions in chemistry.

Greg introduces the concepts of mass, volume, and density, explaining how each is measured and their roles in understanding matter. He demonstrates methods for measuring volume in regular and irregular objects, including geometric formulas and the water displacement method. The lesson highlights the importance of reading the meniscus correctly and wraps up with how to calculate density as a ratio of mass to volume. Relatable examples and practice problems are provided to solidify the concept.

This video covers three critical concepts for evaluating the reliability of measurements: precision, accuracy, and percent error. Using analogies like dartboards and group problem-solving, Greg illustrates the differences between being precise, accurate, both, or neither. He also explains how to calculate percent error to quantify how close a measurement is to the accepted value. The lesson concludes with practical applications and sets the stage for moving on to the next unit on matter and temperature.

The video introduces the foundational concepts of pressure, volume, and temperature, essential for understanding later topics in chemistry. It explains that pressure is the force exerted per unit area and is commonly measured in atmospheres or kilopascals, with a standard conversion of 1 atm = 101.3 kPa. Volume refers to the space an object occupies, typically measured in cubic meters, and temperature reflects the heat energy of particles, measured in Celsius or Kelvin, with Kelvin = Celsius + 273.15. The video also defines standard temperature and pressure (STP) as 0°C (273.15 K) and 1 atm (101.3 kPa), encouraging students to understand and apply these concepts using provided worksheets.

The video introduces the Kinetic Molecular Theory, a model used to predict the behavior of gases by making simplified assumptions. It explains that gases are made of tiny particles in constant, random, straight-line motion, occupying mostly empty space due to their negligible volume. The theory also assumes no intermolecular attractions and that all collisions are perfectly elastic, like bouncing bumper cars. These assumptions describe ideal gases, which differ from real gases that have volume and intermolecular forces. However, real gases behave more ideally under low pressure and high temperature, remembered by the phrase “Please Leave The House” (Pressure Low, Temperature High). The video builds on previous lessons about pressure, volume, and temperature, and prepares students for understanding gas laws in upcoming lessons.

The video explains how pressure, volume, and temperature are mathematically related in ideal gases through several fundamental gas laws. Boyle’s Law shows an inverse relationship between pressure and volume; Gay-Lussac’s Law shows a direct relationship between temperature and pressure; and Charles’ Law shows a direct relationship between temperature and volume. These three can be combined into the Combined Gas Law, which allows solving for a missing variable when pressure, volume, and temperature are involved—requiring temperatures to be in Kelvin. The video also introduces Avogadro’s Law, which states that equal volumes of ideal gases at the same temperature and pressure contain the same number of particles. Together, these laws form the basis for understanding how gases behave under various conditions.

The final video in Unit 1 introduces Graham’s Law of Diffusion and Dalton’s Law of Partial Pressures, rounding out the key concepts of gas behavior. Graham’s Law explains that gases naturally move from areas of high to low concentration, and that lighter gases diffuse faster than heavier ones—a principle students can understand by comparing atomic masses on the periodic table. Dalton’s Law shows that when multiple gases are present in the same container, the total pressure is the sum of the individual (partial) pressures of each gas. Together, these concepts demonstrate how gases move and interact, concluding the unit’s foundational coverage of pressure, volume, temperature, and gas laws.