Density Lab

Density Lab, also known by the names Buoyancy Lab and Buoy Oh Buoy, is a new event rotating in for the 2019 season. It was previously a trial event at the 2018 National Tournament. This events consists of two parts - a written test on density, buoyancy, concentrations, and the behavior of gases, and one or more hands-on tasks relating to those concepts.

Test Description
A Density Lab test consists of two parts, a written test and at least one hands-on task. The written test is 50% to 75% of the total event score, while the hands-on portion contributes the remaining 25% to 50%. The event requires a basic knowledge of chemistry and physics as they pertain to density, concentrations, gas behavior, and buoyancy.

Possible Hands-On Tasks
Students may be required to: Most hands-on tasks will require students to make measurements using provided instruments. For this reason, it is recommended that students practice the hands-on tasks using a variety of instrumentation and techniques.
 * measure or calculate the mass density of a given solid
 * collect a volume of gas and calculate the volume, mass, and mass density
 * determine the number density of multiple objects, such as a bag of brown M&M's
 * determine the mass that a given helium balloon can lift
 * determine the depth to which an object may sink in water
 * determine the density of a material at different temperatures

What is Density?
Density: the degree of compactness of a substance. As shown by the image to the right, is the basic density equation. This equation will be crucial for solving many of the basic density questions in Density Lab.

Gas Laws
Gas Laws are needed so that an understanding of gases behavior and how they pressurize. Most tests will require an understanding of gas behavior.



Archimedes' Principle
Archimedes' Principle will be one of the most important concepts to learn for this event.

Archimedes' Principle: any body completely or partially submerged in a fluid (gas or liquid) at rest is acted upon by an upward, or buoyant, force the magnitude of which is equal to the weight of the fluid displaced by the body. The volume of displaced fluid is equivalent to the volume of an object fully immersed in a fluid or to that fraction of the volume below the surface for an object partially submerged in a liquid. The weight of the displaced portion of the fluid is equivalent to the magnitude of the buoyant force. The buoyant force on a body floating in a liquid or gas is also equivalent in magnitude to the weight of the floating object and is opposite in direction; the object neither rises nor sinks.

Additional Links

 * 2018 Trial Event rules
 * 2012 NYS Trial rules
 * [[Media:Significant Figures.pptx|Significant Figures Tutorial (PPTX)]]