How to Detection Alcohol in Breath, Blood & Urine

Breathalyzer – Alcohol testing devices The Breathalyzer device contains: A system to sample one’s breath and Two glass vials containing the chemical reaction mixture.  A system of photocells connected to a meter measure the color change associated with the chemical reaction. To measure alcohol, a person breathes into the device. The breath sample is bubbled…

Physical Geology & Plate Tectonics

Geology (study of Earth) is important for energy and natural resources, solving environmental problems, building cities and highways, predicting and protecting against natural disasters like earthquakes, volcanic eruptions, landslides, floods Uniformitarianism: fundamental principle “the present is the key to the past” How long? geologic time is measured in billions of years Where and How? After…

Igneous Rocks: Formation, Composition, Naming

Igneous rocks crystallize from molten silicate material called magma that forms at high temperatures and pressures deep in the Earth. Magma rises through the crust and either reaches the surface by volcanoes (extrusive) or cools below surface (intrusive). How Magmas Evolve – according to Bowen’s Reaction Series: discontinuous (different molecular structures of olivine [single tetrahedra],…

Minerals: Silicates, Carbonates, Ores

Minerals are solid chemical compounds that combine to form rocks. They are found in nature and vary in atomic bonding, molecular structure, and element composition, all of which determine their chemical, physical properties and permit their identification. ‑ An infinite number of chemical combinations are possible and almost 4000 natural minerals are known; however, only…

Energy Movement in Ecosystems: Trophic & Energy Pyramid

Organisms can be classified into trophic (feeding) levels depending on how they get their energy. Organisms that get their energy from nonliving sources (sun, organic matter) are called autotrophs (producers) and make up the 1st trophic level. Organisms that get their energy from other living things are called heterotrophs (consumers). Heterotrophs that eat autotrophs make…