2.2 Water Flashcards
How many protons does H2O have?
- 2 Hydrogen atoms (1 proton each)
- 1 oxygen attoms (8 protons)
10 protons total
Covalen bonded molecules that have a slightly potential charge are….
polar
Polar
A charged molecule
attracts other polor or charged compounds
Water molecules connect via weak …… bonds
hydrogen bonds
• consistantly break and reform (transitory)
Cohesian
the action of forming a united whole
- result of polarity of water molecules (and its ability to form hydrogen bonds)
Hydrogens bonds strong or weak?
- Each bond itself is weak
- Each molecule binds to 4 others which makes them stronger (cohesive forces)
How do water droplets form
Because of cohesive forces that are trying to pull the water into the smallest possible volume (a sphere)
Surface Tension
caused by the resistance of cohesive hydrogen bonding when an object tries to penetrate the surface
Adhesian
- The result of polarity of water and its ability to form hyrdrogen bonds
- Water molecules stick to other molecules that are charged or polar
- conjoined bonds give adhesive forces strength
- bond water molecules to a surface and defy gravity
Capillary action
- combo of adhesive forces causing water to bond to a surface and cohesive bonding molecules together
Solvent
- A liquid in which substances are dissolved forming a solution
- Water can dissolve many organic + inorganic substances that have charged or polar regions
Salt water solvent example
- positive Na are surrounded by the negative oxygen region of water molecules
- negative Cl are surrounded by the positive hydrogen regions of water molecule
Specific heat capacity of water
- 2 joules
- raise one gram of H20 by 1C
Heat of vaporization
energy needed to turn a liquid into a gas
Heat of fusion
energy needed to turn a liquid into a solid
Why does water has a high heat of vaporization and fusion?
- Water has many hydrogen bonds, that require energy to form or break
- and that need to be formed/broken to change the state of water
What happens to porteins in high temperatures
They denature which damages tussye and causes enzymes to stop working
What happens when water evaporates?
A lot of energy gets removed from the system
What happens when hydrogen bonds break?
Energy is release, which causing a cooling down effect
Hydrophilic
- Substances that are chemically attracted to water
- Can dissolve in water
- Polar molecules
ex: glucose
Hydrophobic
- Substances that are insoluble in water
- Non-polar molecules
ex: lipids, 95% of blood is plasma is water
Guess this molecule:
- Polar -> soluble
- Hydrophilic (carried by blood plasma)
Glucose
Guess this molecule:
- positive and negative charges (amine and carboxyl/acid groups)
- R group determines the degree of solubility
- carried by the blood plasma
Amino Acids
Guess this molecule:
- non-polar -> hydrophobic
- BUT due to its small size, it is soluble in water but only at high temperatures
• hemoglobin in blood cells carries most of this (very little is carried by plasma)
Oxygen
