Chapter 3 - Water Flashcards
what is the biological
solvent/medium on Earth.
Water
How much percent do organisms yield water in their bodies
Most eukaryotic organisms
are about 70 to 75% water.
What is Astrobiology?
it is the practice of searching water on other places than Earth
Are there any places outside Earth found with water?
If yes, then how many?
To date, there has been about 4 thousand planets that had been identified outside our solar system
Are there any places where water is found inside our solar system? if yes, then label them.
liquid water on Mars
subsurface oceans on Jupiter’s moon
What are the four unique properties of water?
cohesive/adhvesive behavior
expands upon freezing
versatile solvent
ability to modulate temperature
Why does cohesion occur?
Because of hydrogen’s partial charge causing mass attraction to oxygen particles
why does adhesion occur?
because the hydrogen bonding causes it to attract and bond with other material or object
What is capilliary action?
the flow of water through narrow tubes or pathways even against the force of gravity due to its properties of cohesion and adhesion
What is surface tension? what process helps with surface tension>
because of the cohesion boding in water, it creates a strong water surface and slight resistance on the surface
explain the water’s ability to moderate/modulate temperatures
water can absorb or release a large amount of heatwith minimum interference in the temperature because water requires more energy to increase in temperature (high heat capacity)
is heat the fundamental unit of energy?
Yes
explain specific heat of a substance
it’s the amount of heat that has to be absorbed or released to raise/lower the temperature by 1 degree celsius
what is a calorie in terms of heat?
what other process of water (other than expansion upon freezing) helps stabilize its bodies such as lakes on earth?
The process of evaporative cooling, in which when enough heat is absorbed to be converted into gas, the surface of water goes cools down helping the organisms survive in water bodies.
what is the specific amount of heat needed to turn water from liquid state into gas state called?
heat of vaporization
why does water float when it freezes?
because the hydrogen bonding at freezing temperatures creates a rigid lattice crystal structure (chemically), making it less dense than water bodies
at what temperature does ice float on water
at 4 degrees
how does freezed water’s ability to stay afloat help the ecosystem?
the organisms in the water bodies are protected from dying out when temperature turns freezing
during liquid state, do hydrogen bonds create a dynamic environment by constantly changing their covalent bonds from one molecule to another?
yes, this is what creates the fluidity of water
briefly explain concept of a solution
where substances are mixed into one homogenous unit
a solvent is the ____ and a solute is the _____
dissolving the new substance into itself
the substance being dissolved and bonded
what is the solution called when water is the solvent?
aqueous solution
biology is mainly a ____ solution based system
aqeuous
is collodial suspension a real solution? why?
no because the fine particles aren’t fully dissolved into the solvent
what occurs in a collodial suspension in contrast to a regular solution?
the fine particles of the solute seperate from the solvent after a period of time rather than evenly staying distributed into its solvent like shown in a regular solution
do human bodies have collodial suspensions?
yes
what makes water a versatile solvent?
Because of hydrogen molecules in water have partial charges, they often form electrostatic (bonding occuring due to attraction from charges) bonding with the solute. so water’s polarity helps it bond more with its solutes
do different molecules’ hydration shells help them get more dissolved in an aqeuous solution?
yes
hydrophillic vs. hydrophobic
briefly explain
water loving and water hating
why do hydrophobic substances not like to bond with water?
Because they do not have a charge, they are nonpolar and do not need to bond to water and avoid bonding with it
what is dynamic equillibrium?
what is H3O also known as?
H+ (Hydronium Ion)
What is hydroxide ion known as?
OH-
what is ph essentially?
the hydrogen ion concentration in any substance.
the more hydrogen ion conc., the more acidic and the more hydroxyl ion in substance, the more basic.
What is the ph scale’s range?
0-14
at what range of pH do most eukaryotic living beings exist at?
7-8
what is the substance called when there is more OH- concentration in it
basic
what is it called when there is more H+ concentration in a substance
acidic
what’s the relationship between hydrogen ion concentration and pH?
the lower the hydrogen ion concentration, the higher the pH
what range on the pH scale is considered acidic?
0-6
what range on the pH scale is considered basic?
8-14
what does a buffer do?
Buffers are substances that stabilize the pH by minimizing H+ and -OH if either were in excess.
True or false: our bodies naturally contain buffers?
True
how are humans contributing to increasing acidification in Oceans?
Man made developments often release a lot of Co2 which gets absorbed by the ocean which creates carbonic acid. And carbonic acid as a result contributes to ocean acidification due to their acidic properties
what are the consequences of ocean acidification?
The consequences are that many sea life forms cannot live with pH imbalances caused by the acidification which results into destruction of the ecosystem as a whole.
How is acid rain relevant to ocean acidification? How is it caused?
there is no direct correlation between the two. However, acid rains like ocean acidification too destroy the ocean life.
Acid rain caused by burning fossil fuels and the releasing Co2 instead of meeting water like in Ocean acidification, it meets the air.
What are the two main consequences of acid rain? how does the process of acid rain occur?
When fossil fuels are burnt, the released substances collide with air and form strong acids namely **sulfuric and nitric acids **in the air of pH 5.2. And when it rains/hails/snows, these acids fall into the ocean destroying many organisms and habitats. it also destroys the soil chemistry
What is the pH level of acid rains?
6.4
5.2
4.2
5.7
2.3
5.2
another name of acidic rain?
acidic precipitation
