Science C 1-2 Flashcards
Nitrogen fixation (what it is and what organisms do this)
It is required by plants to make substances necessary to life. Fixation- the process of changing free nitrogen so that nitrogen atoms can combine with other elements. Bacteria and alfalfa do this
Nitrogen in the nitrogen cycle
The concentration of useable nitrogen can be
added or taken away from the soil in several
ways:
Nitrated are added by:
- nitrogen fixing plants
- fertilizers/compost/manure
- lightning
Effluent
Effluent is sewage that has been treated in a septic tank or sewage treatment plant. It is also referred to as “trade effluent” or “wastewater.” Purified wastewater released into rivers or lakes
Fertilizer components
Nitrogen, phosphorous, potassium and sometimes sulfur in that order
Sour gas
Natural gas that contains hydrogen sulfide is called “sour” gas. If no hydrogen sulfide is present, the gas is considered “sweet.”
Processes and Activities that Affect Environmental Chemicals
Chemical Cycles (nitrogen for example)
Cellular respiration
Human Activities (like pollution- thermal, chemical, noise)
Fertilizers
combustion reaction
hydrocarbon + oxygen → carbon dioxide + water + energy
what is sewage
wastewater containing dissolved and undissolved material (from bathroom, kitchen, etc.)
septic tank
an underground container where bacteria break down the organic materials before they’re moved out
what does a sewage treatment plant do
treats wastes from homes, businesses, industries, and institutions. It may also treat water from street drains.
What is pH, how does the scale work, each number 10x
pH is a measure of the concentration of hydrogen ions in solution. Indicates the acidity of a solution.
acid (red)
a compound that dissolves in water to form a solution (pH lower than 7). is like a metal, reacts with metals.
base (blue)
a compound that dissolves in water to from a pH over 7. Reacts with acids
acid rain
produced when chemical released from industrial processes combine with water to form acids that fall with the rain. maybe located in the soil
neutralization reaction
Acids can be neutralized by adding a base (liming), and
bases can be neutralized by adding an acid. Neutralization – a reaction where an acid and base
come together to produce water and a salt. This
reaction can be used to neutralize stomach acid.
HCl + NaOH HOH + NaCl
hydrochloric acid + Sodium Hydroxide water + sodium chloride (salt) OR acid + base –> water + salt
A reaction between an acid and a base
where water (HOH) and salt are formed
molecules that contain carbon are
organic. those without carbon are called
inorganic
Organic compounds- carbs, lipids, proteins, nucleic acids
Reaction equation for neutralization
Ca(OH)2(aq) + H2SO4(aq) → CaSO4(s) + 2H2O(l)
calcium hydroxide + sulfuric acid → calcium sulfate + water
Macronutrients
9 elements (nutrients) that are needed in large amounts. the nutrients our body needs in large numbers are called “macronutrients”
Micronutrients
elements (nutrients) needed only in trace amounts
Passive transport
does not require the plant to use energy ex diffusion
Active transport
plants use energy to move molecules from area of low to high concentration EX Amino acids moving along the human intestinal tract.
Diffusion
movement of molecules from an area of high to low concentration EX A drop of food coloring diffuses throughout the water in a glass so that, eventually, the entire glass will be colored.
Osmosis
water moves into plant roots by a special type of diffusion. moves from an area of more water molecules to less through a semi permeable membrane
Optimum Amounts
The amount of a substance that provides an organism with the best health
Hydrolysis
the addition of water breaks down large food particles into its smallest form (breakdown of a substance with water). “Hydro” refers to water and “lysis” means breakdown.
Substrate
the material on which an organism moves or lives.
Biological and chemical indicators of water quality
Biological- using organisms in water to determine quality like bacteria in microbiological and species in aquatic.
Chemical- includes dissolved oxygen, pH, temperature, salinity and nutrients
Freshwater indicators of high and low quality water
A pond that has a variety of organisms has good water quality. Fish and insects
Concentration calculations
concentration of chemicals in the environment is measured in: parts per million, milligrams per kilogram,
Dissolved oxygen
essential for health of organisms
Larve and worms
thrive in polluted water and need dissolved oxygen at 2mg
Effects of nitrogen and phosphorous in water
High concentration of these- increase in algae and green plants, more die because of this. The chemicals cause the ponds oxygen to be depleted due to too much oxygen
toxicity measurement
A measurement called LD50 indicates the amount of the substance that will cause 50% of the population to die
(LD = lethal dose).
The greater the toxicity of a substance the lower the LD50 is. (which has a higher toxicity of LD - 83.3 or 0.00002? The lowest one)
Heavy metals
can enter the environment by acidic water dissolving lead in pipes or fertilizers. mercury in this = poisonous
How to measure air quality
Air is composed of 1% argon, 0.03% carbon, 78% nitrogen, 21% oxygen
Can be measured by measuring the levels of pollutants in the air and estimating the amount of emissions from pollution sources
Pollutants in the air
sulfur dioxide (smog and acid rain), nitrogen oxides (contributes of fossil fuels and acid rain), carbon monoxide (silent and odourless gas from fossil fuels), ground level ozone.
scrubbers
used to reduce sulfur dioxide emissions
causes of thinning of the ozone layer
caused by increasing concentrations of ozone-depleting chemicals (CFC- chlorofluorocarbons)
ozone- how it works and how its helpful + harmful
protects us from harmful ultraviolet rays from space
Harmful- to people who have asthma, all children (lung development), too much could cause lung and breathing damage
Greenhouse gases
Gases in Earth’s atmosphere that trap heat. They let sunlight pass through the atmosphere, but they prevent the heat that the sunlight brings from leaving the atmosphere.
Greenhouse effect vs enhanced greenhouse effect
The greenhouse effect is a natural process that warms the Earth’s surface. When the Sun’s energy reaches the Earth’s atmosphere, some of it is reflected back to space and the rest is absorbed.
Enhanced greenhouse effect- causes temp to increase around the world primarily due to fossil fuels and forest fires - global warming. Results in more energy being absorbed by gases in the atmosphere
combustion and propane equation
propane + oxygen –> carbon + water
similarities and differences in diffusion, osmosis, and active transport.
Diffusion, osmosis and active transport all involve the movement of particles. Though osmosis involves movement of water, active transport moves substances against a concentration gradient, and diffusion is the movement of molecules from an area of high to low concentration
Where is acid rain, bacteria, calcium and leachate found?
Bacteria - sewage
Acid rain- vehicle exhaust
Calcium - rocks
Leachate - landfill sites
Dangers of using pesticides
hh
3 stages of transport in air
- Release of chemicals at the source
- Dispersion of the chemical into the atmosphere
- Deposition of the chemicals in the soil or water
Factors that affect the travel of airborne pollutants?
Airborne pollutants can be carried away by..
wind or no wind
precipitation (rain or snow)
weight of pollutant (heavier particles will be deposited closer to source
Carried away by wind and ocean currents
Transport in ground water (this is something that transports materials or pollutants)
Groundwater zone: All space between soil grains
is filled with water.
The top of this zone is called the water table.
Groundwater moves slowly compared to rivers.
This allows chemicals to build up (become concentrated)
because they cannot disperse quickly.
Transport in surface water
Multiple sources of chemical toxins travel though water.
Permeable vs Impermeable soils
Permeable surfaces (also known as porous or pervious surfaces) allow water to percolate into the soil to filter out pollutants and recharge the water table. Impermeable/impervious surfaces are solid surfaces that don’t allow water to penetrate, forcing it to run off.
Transport of hydrocarbons in soil
Carried by water, they fill the pores in grains, and are toxic.
Dispersion
the scattering of a substance away from its sources E.x.
Dilution
reduces the concentration of a pollutant by mixing the polluting substance with large amounts of water or air.
Biodegradation, Factors affecting biodegradation, Another method of encouraging biodegradation in soil involves
Breakdown of materials by organisms like earthworms, bacteria, and fungi. Bio refers to living things and degrade means to break up.
Temperature, moisture, acidity, oxygen levels, pH, and
nutrients (eg. Hot temperature speeds it up).
planting vegetation
Bacteria in Aerobic biodegradation and Anaerobic
Aerobic: Oxygen is required for breakdown.
Anaerobic: No oxygen required.
Phytoremediation
a techniques that can be used to reduce the concentration of harmful chemicals in soil or ground water
photolysis
the breakdown of compounds by sunlight. Example: photodegradable plastic
things that could happen to the water being watered anywhere
- evaporates
- soaks in soil
- runoff to stream
- move into ground water
Chemical pollutants carried away from sources
through wind or ocean currents
Water through sand and clay
water moves more easily through sand than through clay
ways of reducing the concentration of pollutants
- dispersion -dilution -biodegradation -photolysis
- phytoremediation
Biomagnification
An increase of a chemical or elements as it moves up the food chain
Examples of household hazardous products
household cleaners
fertilizers
paint
Safe and unsafe practices with hazardous household chemicals
Leave on label
Never store gas in glass containers
Keep upright
Never mix
Disposal of household hazardous products
Take to disposal sites or follow garbage guidelines
MSDS
Material safety data sheets
- Gives detailed description of product
- describes precautions
Process where acidic snow melts and acidic water enters the waterways
spring acid shock
