15B Midterm Flashcards
Why is low pH in AMD harmful?
Acid incurs dissolution, H+ corrodes cell membranes. Also mobilizes metals, converting them to ions, making them more soluble.
What can be used to neutralize pH?
CaCO3 (limestone) can be used to neutralize pH. Other bases can be used as well.
What is AMD?
Mining exposes sulfur-bearing minerals to atmospheric O2, H2O, and acidophili iron-oxidizing bacteria. This results in sulfuric acid, dissolved iron, and ferric hydroxide. Sulfuric acid dissolves heavy metals and forms acidic pH solution with enters soil, surface water, and groundwater.
How to calculate pH
pH = -log[H+] or [H+] = 10^-pH
Why is nuclear power so powerful?
Radioactive isotopes high on periodic table are useful because they have a large, unstable nucleus, which can be split when hit by a high-speed n, releasing a lot of energy. A single neutron can initiate a chain reaction because it hits a U-235, which splits into other atoms and neutrons, which hit other U-235 nuclei.
Why does nuclear power generate so much waste?
The products from nuclear power constitute diverse waste which decay at different rates. Some decay quickly and are more immediately harmful to human health, such as U tailings leaching into water, releasing radiation in the body.
What are mine tailings?
Waste leftover after target mineral is extracted. It is composed of crushed rock, water, and trace metals. Often acidic and can leach.
What is stoichiometry?
The balancing of equations and conversion between moles and mass.
What are the types of radioactive decay?
Alpha - 4/2 He particle
Beta - 0/-1 electron
Gamma - 0/0 y (photon)
What is an oxide?
An oxide is a compound containing at least one oxygen atom and one other element. They are termed as oxides because they exist with only one other element.
What are aerosols? What is an example?
Suspensions of small solid particles in gas or liquid. They are the most complicated and least understood forcing on climate change. They can scatter and/or absorb radiation.
Why do we need more neutrons to balance out large nuclei?
To balance out all Z pushing each other apart.
What is an acid? What is a base?
An acid is a substance that forms H+ ions when dissolved in water. A base is a substance that can accept H+ ions in water and neutralize an acid.
How do we predict rad?
See notes
What are catalysts? Draw this.
Bacteria can catalyze the AMD rxn - speeding it up, lowering activation energy.