ch 8 science test

energy use in US

how coal forms

Coal forms over millions of years from the remains of dead plants in swampy environments. When plants die, they sink and are buried by layers of sediment, and the resulting pressure and heat from deep burial transform the plant matter into peat and then coal.

how oil (petroleum) forms

Petroleum forms over millions of years from the remains of ancient marine plants and animals, which are buried under layers of sand, silt, and rock. Intense heat and pressure from these overlying layers transform the organic material into a mixture of hydrocarbons.

how natural gas forms

when ancient remains of plants and animals are buried under layers of sediment, and subjected to millions of years of heat and pressure deep within the Earth. This immense heat and pressure transforms the organic matter into hydrocarbons, primarily methane, which becomes trapped in porous rock formations. 

what are the uses of coal

to generate electricity, critical fuel for producing steel, coal is used in the production of cement, and its by-products are used to create a variety of chemicals and products, including dyes, soaps, plastics, and some medicines. 

what are the uses of oil (petroleum) 

transportation fuels like gasoline, diesel, and jet fuel; heating and electricity generation

what are the uses of natural gas

electricity generation, heating homes and buildings, and cooking

how do power plants produce electricity from fossil fuels

burning the fuel to create heat, which turns water into high-pressure steam. This steam spins a turbine, and the turbine's rotation drives a generator to produce electricity through electromagnetic induction.

combustion reactions

a chemical process where a substance, the fuel, reacts rapidly with an oxidant, usually oxygen, to produce heat and light. When a hydrocarbon fuel (containing carbon and hydrogen) undergoes complete combustion, the products are carbon dioxide and water.

• What are the products and reactants of a combustion reaction?

the reactants are a fuel and an oxidizer, which is almost always oxygen. The products of complete combustion are carbon dioxide and water

balancing combustion reactions

start by balancing the carbon atoms, then the hydrogen atoms, and finally the oxygen atoms 

using control rods 

fusion vs fission

Fission splits heavy atoms, releasing energy and producing long-lived radioactive waste, while fusion joins light atoms to form a heavier one, releasing even more energy with less radioactive waste

nuclear fuel

enriched uranium, is a substance used to generate energy in nuclear reactors through controlled nuclear fission

• How a nuclear power plant produces electricity

through a process called nuclear fission, where the heat from splitting atoms is used to create steam that spins a turbine. This is a three-step process: First, a nuclear reactor heats water through controlled fission to create steam. Second, the steam turns a turbine, which is connected to a generator. Third, the generator spins to produce electricity. 

• Why are control rods so important?

they are essential for controlling the nuclear fission rate in a reactor, which allows them to safely regulate power and shut down the reactor in emergencies

advantages and risks of nuclear power

advantages: a reliable, low-carbon energy source

risks: challenge of radioactive waste disposal and the potential for severe accidents

how solar energy works

the suns rays beat down onto solar panels. The panels harness the energy and powers a generator

how hydroelectric dams generate electricity

by using the force of falling or flowing water to spin turbines, which are connected to generators that convert the mechanical energy into electrical energy

how wind generate electricity

the wind blows and spins the turbines on the wind turbines that powers a generator.

how tidal power produces energy

the rising and lowering tides spin underwater turbines which generate electricity

how biomass generates electricity

through direct combustion, where burning the organic material heats water to create high-pressure steam. This steam then spins a turbine, which is connected to a generator that produces electricity

how geothermal power generates electricity

using heat from the Earth to spin a turbine connected to a generator

where can solar energy be used 

any place that has constant exposure to the sun during the day

where can hydroelectric tidal be used

in flowing bodies of water that can sustain a turbine

where can tidal energy be used

in places along the coast

where can wind energy be used

in windy places that have wide open fields

where can biomass energy be used

heating and electricity generation for residential, commercial, and industrial buildings, as well as producing liquid biofuels for transportation

where can geothermal energy be used

countries like Iceland, El Salvador, and the Philippines producing a significant portion of their electricity from it, while applications like heating buildings and greenhouses are common in many places, including the United States

natural greenhouse effect

• gases in the atmosphere like CO2, methane, nitrous oxide, and water vapor trap heat from the sun and make Earth livable

human enhanced greenhouse effect

• even more major greenhouse gases: H2O (water vapor), CO2 (carbon dioxide), CH4 (methane), O3 (ozone), N2O (nitrous oxide) are released into the atmosphere making the air warmer

surfaces with high albedo

fresh snow, ice, light-colored sand, and urban surfaces like white roofs and new concrete. 

surfaces with low albedo

dark surfaces like forests, oceans, asphalt, and soil

carrying capacity

the maximum population size of a species that an environment can sustainably support over time

pollutants in agriculture

nutrients like nitrogen and phosphorus from fertilizers, various pesticides, sediment from soil erosion, and pathogens and waste from livestock

effects of deforestation

loss of biodiversity, contributing to species extinction and habitat loss for countless plants and animals. It also causes climate change, soil erosion and degradation, disrupts water cycles, and can lead to flooding and drought.

water pollution

harms human health through diseases like cholera and typhoid and long-term issues like cancer, hormonal disruptions, and organ damage

ocean acidification

ongoing decrease in the ocean's pH due to the absorption of excess atmospheric carbon dioxide from human activities, primarily fossil fuel burning. This process lowers the pH and reduces the availability of carbonate ions, which are essential for many marine organisms to build shells and skeletons, threatening food chains and marine ecosystems. 

air pollution

causing respiratory and cardiovascular diseases like asthma, bronchitis, heart attacks, and strokes, and can lead to premature death. It also harms the environment by damaging ecosystems, contributing to climate change, and reducing visibility

photochemical smog

a type of air pollution that forms when nitrogen oxides and volatile organic compounds react in the atmosphere with sunlight. This process creates a brownish haze over cities, particularly during warm, sunny days with little wind. 

CFCs and Ozone interaction

(CFCs) react with ozone in the stratosphere through a catalytic chain reaction initiated by ultraviolet (UV) radiation that breaks the CFC molecule into chlorine radicals. The chlorine radical then repeatedly destroys ozone molecules by converting them to oxygen and regenerating itself, leading to the depletion of the protective ozone layer. 

causes of ocean acidification 

absorption of excess atmospheric carbon dioxide from human activities like burning fossil fuels, deforestation, and agriculture. When CO2cap C cap O sub 2𝐶𝑂2 dissolves in seawater, it forms carbonic acid, which then releases hydrogen ions, lowering the ocean's pH and making it more acidic. This process also reduces the availability of carbonate ions, which are essential for marine organisms to build shells and skeletons. 

what impacts does it have on marine life

reduces the availability of carbonate ions, which are essential for marine organisms to build shells and skeletons, resulting in weaker, smaller shells of marine organisms.

what is one example on a sea animal impacted

sea urchins

will warmer or colder oceans become more acidic

Colder oceans become more acidic

because cold water can absorb more dissolved carbon dioxide than warm water