Water Flashcards
Properties of water
1) at sea level, boils at 100 degrees and freezes at 0 degrees
2) the boiling point decreases (lower then 100) at higher elevations (lower atmospheric pressure). For that reason, an egg takes longer to cook because the water isn’t as hot
Water polarity and net charge?
water is polar because of the unequal sharing of electrons between oxygen and hydrogen, but neutral because the total number of positive protons and negative electrons are equal!
Hydrogen bonds between water molecules
Hydrogen bonds form between the highly electronegative atom and a hydrogen atom. The oxygen of one water attracts the hydrogen of another
* 1 hydrogen bond is weak, but many are strong
Cohesion
The attraction of molecules of the same substance. Results in surface tension, which create a film on the surface, which allows bugs to walk in water
Adhesion
Attraction between molecules of a different substance. Water will create a hydrogen bond with these substances
Capillary action: water molecules will climb each other when in a small tube
What is high specific heat
The amount of heat required to rise or lower 1g of a substance 1 degree
Water resists temperature change
Water is able to absorb or release large amounts of heat without rising it’s only temperature
Benefits of high specific heat of water
Stabilizes earth temperature, as it can absorb and release large amounts of heat, while only slightly increasing its own temperature. Life couldn’t exist if the temperature was constantly changing due to the temperature on the day
What is high heat of viperization
The amount of energy required to convert 1g of a substance to a liquid to gas
In order for water to evaporate, hydrogen bonds between molecules has to be broken
Aa water evaporates, it removes a lot of heat with it (cooling effect)
Water vapour keeps the earth warm
Density of a water
Water is less dense as a solid compared to it’s liquid state because the liquid state has hydrogen bonds that are always being broken and reformed, while freezing water causes it form a crystal lattice where molecules are fixed and set at a certain distance
Water is considered the solvent…
Of life because can can dissolve many things
When a ionic compound is dissolved
It disperses into ions, making the solution
What are aqueous solutions?
A type of solution where water is the solvent
Why is water a good solvent
Due to its small size and polar molecule allow it to dissolve charged and polar molecules/ ions
1 water molecules out of 550 million..
Breaks down in a H+ and OH- ion
The pH scale indicates
The concentration of H+ ions. It ranges from 0-14, 7 being neutral, below 7 being acidic, and greater then 7 being basic. Each level on the scale is a multiple of 10
A strong acid has a ph of
1-3, produces lots of H*
A strong base has a ph of
11-14, producing a lot of OH-
The strength of a acid or a base is determined by
How much it is dissociated into a solution. Ex HCL -> H+ + Cl-
What is a buffer
A buffer is a solution which contains a weak acid or base, and when you add a strong acid or base to it, it neutralizes it preventing any pH drops
