Chemistry in Context: Radiation, Ozone, and Climate Change

Dobson Unit

Measurement unit for ozone concentration.

Wave-Particle Duality

Concept that light exhibits both wave and particle properties.

UV Index

Scale indicating strength of UV radiation.

Electromagnetic Spectrum

Range of all types of electromagnetic radiation.

Wavelength

Distance between consecutive peaks of a wave.

Frequency

Number of wave cycles passing a point per second.

UV Radiation

Radiation with shorter wavelengths than visible light.

Quantum of Energy

Smallest discrete unit of energy.

Photons

Particles representing a quantum of light. Wave packets of energy.

Dynamic Steady State

Balance between O2 and O3 in the stratosphere.

Ozone Layer

Region in atmosphere protecting from UV radiation.

Chlorofluorocarbons (CFCs)

Human-made compounds harmful to ozone layer.

Montreal Protocol

International treaty to phase out CFC production.

Sunscreens

Products that block UV radiation from skin.

Carbon Cycle

Movement of carbon atoms through various compounds.

Avogadro's Number

6.02 x 10^23, number of atoms in a mole.

Mass Number

Total number of protons and neutrons in an atom.

Isotopes

Atoms of the same element with different masses.

Greenhouse Effect

Trapping of heat in the atmosphere by gases.

Greenhouse Gases

Gases that absorb and emit infrared radiation.

Infrared Radiation

Type of radiation that greenhouse gases interact with.

Molecular Mass

Sum of the atomic masses in a molecule.

Covalent Bond

Chemical bond formed by sharing electrons.

Octet Rule

Atoms tend to bond until they have eight electrons.

Resonance Structures

Different ways to represent a molecule's structure.

Ozone Depletion

Reduction of ozone layer due to chemicals.

Biological Sensitivity

Vulnerability of DNA to UV radiation.

Chemical Formula

Representation of a molecule's composition.

Climate

Long-term atmospheric conditions in a region.

Weather

Short-term atmospheric conditions at a specific time.

Fossil Fuels

Natural fuels formed from decomposed organisms.

CO2 Monitoring

Tracking carbon dioxide levels over time.

Industrial Revolution

Period marked by increased industrial activity and emissions.

Global Surface Temperatures

Average temperature of Earth's surface over time.

Climate Predictions

Forecasts about future climate conditions.

IPCC

United Nations panel on climate change.

Sea Ice Disappearance

Loss of ice in polar regions due to warming.

Sea-Level Rise

Increase in ocean levels due to melting ice.

Biodiversity Loss

Reduction in variety of life forms.

Ecological Footprint

Measure of human demand on Earth's ecosystems.

Potable Water

Water safe for drinking and cooking.

Aqueous Solution

Solution where water is the solvent.

Hydrogen Bonding

Attraction between water molecules due to polarity.

Specific Heat

Amount of heat required to raise temperature.

Desalination

Process of removing salt from seawater.

Reverse Osmosis

Water purification method using a semipermeable membrane.

Acid Rain

Rain with a pH below 5, harmful to ecosystems.

pH Scale

Scale measuring acidity or basicity from 0 to 14.

Neutralization

Reaction producing equal concentrations of H+ and OH-.

Electrolyte

Substance that conducts electricity in solution.

Ocean Acidification

Decrease in ocean pH due to CO2 absorption.

Contamination

Presence of harmful substances in water.

Water Footprint

Total volume of freshwater used by an individual.

Chlorination

Water treatment process using chlorine for disinfection.

Fluoridation

Addition of fluoride to water for dental health.

Life Straws

Portable filters removing contaminants from water.

How many protons are in an atom?

Same as the atom’s atomic number

How many electrons are in a neutral atom?

It’s the same as the number of protons

How many neutrons are in an atom?

Use the mass number (P+N=mass number)

Waves have energy but

no mass

Hertz

the unit of frequency

Greenhouse effect

the process by which atmospheric gases trap and return infrared radiation radiated by the earth

IR radiation

Less energetic than UV radiation, causing vibrations rather than breaking bonds

How do you balance a chemical equation?

C3H8 + 5O2 = 4H2O + 3CO2

atomic number

#of protons found in the nucleus

Nucleus

composed of protons and neutrons

E = hv

Relationship between quantized energy and frequency

UV-A, UV-B, UV-C

C being the strongest (highest energy), A being the weakest.

UV-C

UV radiation completely absorbed by Ozone layer

troposphere, stratosphere, mesosphere, thermosphere, and exosphere

regions of the atmosphere in order of closeness

duet rule

hydrogen and helium may have no more than 2 electrons in their valence shells

mass number

P + N

single bond

a covalent bond that occurs when 2 atoms share one electron pair

stable state

all elements want 8 electrons (chemical bonding)

double bond

in which two electron pairs are shared between the two atoms

O = O - O

Ozone’s resonance structure

Zinc oxide

best protection from UV-a and UV-B

Molar mass

mass of a substance (in grams) divided by the number of moles of a substance

optimal temperature on earth

15 degrees C

linear molecules

Nitrogen (N2) and Oxygen (O2)

greenhouse gases

vibrate, stretch, and bend compared to rigid non-greenhouse gases

IR sensitive gases

CO2, H2O, CH4, O3, N2O, CFCs, and CO

Nitrogen (N2) and Oxygen (O2)

NOT IR sensitive gases

top 5 CO2 emitters

China, USA, Russia, India, and Japan

Polar

water is a [ ] molecule

polar covalent

water is made of BLANK BLANK bonds

less dense

ice is BLANK BLANK than water

molarity

grams/liter of solution

polar compounds

sugar

polar compounds

dissolve in water

non-polar covalent compounds

do not dissolve in water

surfactants

help mix oil and water

surfactants

soaps and detergents

antacids

bases

Neutral solutions

•  neither acidic nor basic; that is, they have equal

• concentrations of H+ and OH- ions

acidic solution

[H+] > [OH-] ; sour

basic solution

[H+] < [OH-] ; bitter

sulfur dioxide (SO2)

caused by the burning of coal, steel mills, heavy industries

nitric dioxide (NO2)

caused by heavy traffic, dense urban areas

anthropogenic emissions

the release of greenhouse gases (GHGs) and pollutants into the atmosphere as a result of human activities