General Chemistry

Samples of Elements

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First day of Gen Chem: Metals and non-metals; solids, liquid and gas elements; compound of elements.
[In-Depth Description]

Weighing Moles

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Several samples are weighed on the balance; each is a mole.
[In-Depth Description]

Hydrogen Balloon and H₂ + O₂ Explosion

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A balloon of hydrogen gas is ignited, followed by balloon with a stoichiometry mixture of hydrogen and oxygen gas.

Reacting Particles or Potential Well on a Track

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Balls are rolled on a track to show two particles reacting or a potential well showing the bond between two atoms. See High Road, Low Road for the picture of the apparatus.

Benjamin Franklin's Thunder House

[L | t+ | ★★★★]
Ben Franklin's thunder house is blown apart by "lightning" causing a explosive chemical reaction.
[In-Depth Description]

Photochemical Reaction of Hydrogen and Chlorine

[ S | t++ | ★★★★ ]
Different colors of LED light illuminate a  small corked test tube with no reaction. Ultraviolet light causes an explosion that shoots the cork across the room.
[In-Depth Description]

Liquid Nitrogen Trash Can

[ L | t+ | ★★★★] An inverted trash can is launched into the air by an exploding bottle of liquid nitrogen.
[In-Depth Description]

Conductivity of Solutions

[M | t+ | ★★★ ]
A light bulb is lit when the conductivity probe is immersed in an ionic solution.
In-Depth Description]

Precipitation of Silver Chloride

[S | t | ★★★]
Sodium chloride solution is added to silver nitrate solution and a white precipitate of silver chloride is instantly formed.
In-Depth Description]

Precipitation of Lead Iodide

[S | t | ★★★]
Potassium iodide solution is added to lead nitrate solution, and bright yellow lead iodide precipitates.
In-Depth Description]

Equilibrium of Iron (III) Thiocyanate

[S | t+ | ★★★]
Le Chatelier’s principle is demonstrated by color changes that result from the addition of solid chemicals to the iron (III) thiocyanate equilibrium system.
[In-Depth Description]

BromoThymol Blue to Yellow by Breath

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A person's acid breath changes a bromothymol blue indicator solution from blue to yellow.
[In-Depth Description]

Acid Base Titration

[M | t | ★★ ]
Titration of 0.1M sodium hydroxide against 0.1M hydrochloric acid, with a phenolphthalein endpoint.

Buffer Solution

[S | t+ | ★★★★ ]
The ability of a buffer to resist changes in pH is colorfully shown by adding strong acid and base to water and buffer solution with universal indicator.
[In-Depth Description]

Metals in Acid

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Curls of zinc and magnesium are dropped into 2M hydrochloric acid, and bubbles observer'd.
[In-Depth Description]

Dilution

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Two-liter volumetric flask mostly full of distilled water, dye and pipette to add, and distilled water to the line.

Marshmallow in Vacuum

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A polycarbonate bell jar is loaded with marshmallow(s), and the air evacuated. Expansion ensues, followed by frantic shrivelling when the air is re-introduced.

Hot and Cold Gas in Balloons

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A balloon is dropped in boiling water, and another balloon is cooled with liquid nitrogen to demonstrate the effect of temperature on volume of gas in a balloon.
[In-Depth Description]

Limiting Reagent, Vinegar or Baking Soda?

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Vinegar and two different amounts of baking soda in plastic soda bottles with balloons.
[In-Depth Description]

Speed of Sound in Helium and SF₆

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Cylinders of helium and sulfur hexafluoride with tubing and regulators set to play an organ pipe, which will also be played by the lecturer to demonstrate the speed of sound in air.

Specific Heat of Air and Water

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Two clean plastic cups, one filled with room temperature water, the other empty, for a student to test with their finger.
[In-Depth Description]

Hydrogen Peroxide Decomposition by Iodide

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Hydrogen peroxide 30% in a large round flask decomposes to boiling water and oxygen when postassium iodide is added.
[In-Depth Description]

Vibrating String

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A 1.5m length of string driven at one end and fixed at the other shows standing waves for various driving frequencies.
[In-Depth Description]

Tower of Spectra

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Assembly of three gas discharge tubes and white light source for spectral analysis with diffraction gratings.
[In-Depth Description]

Photoelectric Effect

[L | t++ | ★★★ ]
Discharge of electroscope using carbon arc UV source.
[In-Depth Description]

Wooden Orbital Models

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Collection of 16 wooden models of atomic orbital states s, p, d, and f.
[In-Depth Description]

Molecular Models

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Molecular models. We have them. We make them. In this case, long hydrocarbon, water, and C60.

Reactions of Li, Na, and K with Water

[ L | t+ | ★★★★ ]
Lithium, sodium, and potassium undergo reactions with water.
[In-Depth Description]

Contact Us

Mailing Address: Lecture Demonstration Services, Science Center, Rm B-08A, 1 Oxford Street, Cambridge, MA 02138
Campus Location: Science Center B-08A | Tel: (617) 495-5824 | Email: scidemos@fas.harvard.edu