H2O Just Add Water : Water Molecules Flashcards
Is water an organic molecule?
NO, water is not an organic molecule even though it is the molecule that supports all life.
Why is water extremely important?
Because of the bonds it can make?
What allows water molecules to form hydrogen bonds?
Their polarity : Water is a polar molecule with partial charges.
Cohesion
The bonding of a high percentage of the molecules neighboring molecules : Helps pull water, and defies gravity : When water sticks to Water
Why is water a good SOLVENT?
Because of water’s Polarity
When water dissociates, which two ions will be formed?
Hydroxide and Hydronium
What types of molecules have an AFFINITY for water?
Polar/Hydrophilic
If a solution has a HIGH concentration of H+ ions, then what will it be considered as?
An Acid.
Why does Ice float on top of water?
Ice floats on top of water because the water molecules are bonded very uniformly/orderly, making the ice less dense.
How does surface tension work?
Hydrogen bonds at the top of the water are so strong, that’s why it’s hard for bugs to break surface tension as well as leaves etc.
Adhesion
When water sticks to something other than water.
Copilary Reaction
Cohesion and Adhesion together.
Evaporation
Liquid to gas : takes a lot of energy
Solvent
Does the dissolving to the solute
Dissociate
When water breaks apart : some waters then steal the hydrogen of another water creating hydronium and hydroxide.
More Hydronium creates what?
ACID
More Hydroxide creates what?
BASE
Moderation Temperature
Water moderates air temp. by absorbing heat from warm air and releasing stored heat to air that is cooler.
Ice acts like what?
an insulator
What happens when Acids & bases interact with Polar molecules
When they interact it can affect the structures, changing certain functions
Heat is absorbed when?
When hydrogen bonds break.
Heat is released when?
When hydrogen bonds form.
Define Heat
A measure of the total amount of kinetic energy due to molecular motion.
Define Kinetic energy
Energy of Motion
The Solvent of Life : Why is water a versatile solvent?
due to its polarity, it can form aqueous solutions.
Hydrophilic
Has a liking/affinity for water
Hydrophobic
Does not have a liking/affinity for water.
What does disassociation lead to?
Leads to acidic and basic conditions that affect living organisms.
Acid
Any substance that INCREASES the Hydorgen ion concentration of a solution (HYDRONIUM)
Base
any substance that REDUCES the hydrogen ion concentration of a solution and INCREASES the concentration of HYDROXIDE IONS
What is the pH of a solution determined by?
determined by the relative concentration of hydrogen ions. (low in acid, high in base)
What is the internal pH of most living cells?
close to pH 7
Buffers
Substances that minimize or “Buff” changes in the concentrations of hydrogen and hydroxide ions in a solution.
- Buffers consist of an acid-base pair that reversibly combines with hydrogen ions.
Acid Precipitation
Rain, Snow, or fog, with a pH lower than pH5.6
- caused by the mixing of different pollutants with water in the air.
