Students observe capillary action in glass tubes of varying sizes. Then they use the capillary action to calculate the surface tension in each tube. They find the average surface tensions and calculate the statistical errors.

Small molecules are chemicals that can interact with proteins to affect their functions. Learn about the structure and biological functions of various small molecules like sugar and caffeine. Also featured on the HHMI DVD, Scanning Life's Matrix: Genes, Proteins, and Small Molecules. Available free from HHMI.

Students are challenged to use computer-aided design (CAD) software to create “complete” 3D-printed molecule models that take into consideration bond angles and lone-pair positioning. To begin, they explore two interactive digital simulations: “build a molecule” and “molecule shapes.” This aids them in comparing and contrasting existing molecular modeling approaches—ball-and-stick, space-filling, and valence shell electron pair repulsion (VSEPR)—so as to understand their benefits and limitations. In order to complete a worksheet that requires them to draw Lewis dot structures, they determine the characteristics and geometries (valence electrons, polar bonds, shape type, bond angles and overall polarity) of 12 molecules. They also use molecular model kits. These explorations and exercises prepare them to design and 3D print their own models to most accurately depict molecules. Pre/Post quizzes, a step-by-step Blender 3D software tutorial handout and a worksheet are provided.

In this activity, learners explore the question "What is paper?" Learners discover the processes and materials required to make paper while experimenting with different recycled fibers and tools.

This resource is a collection of videos taught using a LightBoard, a specialized glass that creates a transparent white board. It teaches scientific principles to quantitatively assess the risk of airborne transmission of COVID-19 in indoor spaces based on factors such as the occupancy, time, room geometry, mask use, ventilation, air filtration, humidity, respiratory activities, etc., as well as how these factors interact. This collection is suitable for learners with some undergraduate-level training in STEM, although some videos may also be accessible to the general public. Graduate students and professionals can watch optional videos with more challenging mathematics. A full MITx course with problems and bonus content is available for free on MITx Online.

This course introduces dynamic processes and the engineering tasks of process operations and control. Subject covers modeling the static and dynamic behavior of processes; control strategies; design of feedback, feedforward, and other control structures; and applications to process equipment.
Dedication
In preparing this material, the author has recalled with pleasure his own introduction, many years ago, to Process Control. This OCW course is dedicated with gratitude, to Prof. W. C. Clements of the University of Alabama.

This course teaches principles of flow, transport, and reaction processes in the natural subsurface.

Add different salts to water, then watch them dissolve and achieve a dynamic equilibrium with solid precipitate. Compare the number of ions in solution for highly soluble NaCl to other slightly soluble salts. Relate the charges on ions to the number of ions in the formula of a salt. Calculate Ksp values.

Students learn how to classify materials as mixtures, elements or compounds and identify the properties of each type. The concept of separation of mixtures is also introduced since nearly every element or compound is found naturally in an impure state such as a mixture of two or more substances, and it is common that chemical engineers use separation techniques to separate mixtures into their individual components. For example, the separation of crude oil into purified hydrocarbons such as natural gas, gasoline, diesel, jet fuel and/or lubricants.

Students are given a variety of materials and asked to identify each material as a solid, liquid or gas. They use their five senses ‰ŰÓ sight, sound, smell, texture and taste ‰ŰÓ to identify the other characteristics of each item.

Students are introduced to superhydrophobic surfaces and the "lotus effect." Water spilled on a superhydrophobic surface does not wet the surface, but simply rolls off. Additionally, as water moves across the superhydrophobic surface, it picks up and carries away any foreign material, such as dust or dirt. Students learn how plants create and use superhydrophobic surfaces in nature and how engineers have created human-made products that mimic the properties of these natural surfaces. They also learn about the tendency of all superhydrophobic surfaces to develop water droplets that do not roll off the surface but become "pinned" under certain conditions, such as water droplets formed from condensation. They see how the introduction of mechanical energy can "unpin" these water droplets and restore the desirable properties of the superhydrophobic surface.

Surface tension accounts for many of the interesting properties we associate with water. By learning about surface tension and adhesive forces, students learn why liquid jets of water break into droplets rather than staying in a continuous stream. Through hands-on activities, students learn how the combination of adhesive forces and cohesive forces cause capillary motion. They study different effects of capillary motion and use capillary motion to measure surface tension. Students explore the phenomena of wetting and hydrophobic and hydrophilic surfaces and see how water's behavior changes when a surface is treated with different coatings. A lotus leaf is a natural example of a superhydrophobic surface, with its water-repellent, self-cleaning characteristics. Students examine the lotus effect on natural leaves and human-made superhydrophobic surfaces, and explore how the lotus leaf repels dewy water through vibration. See the Unit Overview section for details on each lesson in this unit.

Students extend their understanding of surface tension by exploring the real-world engineering problem of deciding what makes a "good" soap bubble. Student teams first measure this property, and then use this measurement to determine the best soap solution for making bubbles. They experiment with additives to their best soap and water "recipes" to increase the strength or longevity of the bubbles. In a math homework, students perform calculations that explain why soap bubbles form spheres.

Students learn about the basics of molecules and how they interact with each other. They learn about the idea of polar and non-polar molecules and how they act with other fluids and surfaces. Students acquire a conceptual understanding of surfactant molecules and how they work on a molecular level. They also learn of the importance of surfactants, such as soaps, and their use in everyday life. Through associated activities, students explore how surfactant molecules are able to bring together two substances that typically do not mix, such as oil and water. This lesson and its associated activities are easily scalable for grades 3-12.

Students see how different levels of surface tension affect water's ability to move. Teams "race" water droplets down tracks made of different materials, making measurements, collecting data, making calculations, graphing results and comparing to their predictions and the properties of each surface, determining which surface exhibits the highest (or lowest) level of surface tension with water. They apply their results to make engineering recommendations for real-world applications.

Students experience the engineering design process as they design, fabricate, test and redesign their own methods for encapsulation of a (hypothetical) new miracle drug. As if they are engineers, teams make large-size prototypes to test proof of concept. They use household materials (tape, paper towels, plastic wrap, weed-barrier fabric, glues, etc.) to attach a coating to a porous "shell" (a perforated plastic Wiffle® ball) containing the medicine (colored drink mix powder). The objective is to delay the drug release by a certain time and have a long release duration—patterned after the timed release requirements of many real-world pharmaceuticals that are released from a polymer shell via diffusion in the body. Guided by a worksheet, teams go through at least three design/test iterations, aiming to achieve a solution close to the target time release constraints.

Turbulent flows, with emphasis on engineering methods. Governing equations for momentum, energy, and species transfer.
Turbulence: its production, dissipation, and scaling laws. Reynolds averaged equations for momentum, energy, and species transfer. Simple closure approaches for free and bounded turbulent shear flows. Applications to jets, pipe and channel flows, boundary layers, buoyant plumes and thermals, and Taylor dispersion, etc., including heat and species transport as well as flow fields. Introduction to more complex closure schemes, including the k-epsilon, and statistical methods in turbulence.

Students are presented with the concepts of wetting and contact angle. They are also introduced to the distinction between hydrophobic and hydrophilic surfaces. Students observe how different surfaces are used to maintain visibility under different conditions.

Students learn how common pop culture references (Harry Potter books) can relate to chemistry. While making and demonstrating their own low-intensity sparklers (muggle-versions of magic wands), students learn and come to appreciate the chemistry involved (reaction rates, Gibb's free energy, process chemistry and metallurgy). The fun part is that all wands are personalized and depend on how well students conduct the lab. Students end the activity with a class duel a face-off between wands of two different chemical compositions. This lab serves as a fun, engaging review for stoichiometry, thermodynamics, redox and kinetics, as well as advanced placement course review.

Test the pH of things like coffee, spit, and soap to determine whether each is acidic, basic, or neutral. Visualize the relative number of hydroxide ions and hydronium ions in solution. Switch between logarithmic and linear scales. Investigate whether changing the volume or diluting with water affects the pH. Or you can design your own liquid!