UNIT 1: topic 1 "Structure of water and hydrogen bonding"
What is an example of adhesion?
Meniscus in a graduated cylinder
What kind of bond is a hydrogen bond?
inter-molecular: bond that forms between molecules
What forms of covalent bonds can form in between molecules?
single bonds (one pair of shared electrons), double bonds (two pairs of shared electrons), triple bonds (three pairs of shared electrons)
What properties could not exists/ be less effective if oxygen and hydrogen had the same electronegative
-Cohesion -Adhesion -Surface Tension -Capillary Action
Where are ionic bonds most commonly found? why?
Between a non metal and a metal. The metal transfers electrons to the nonmetal
What does it mean to say that oxygen is more "electronegative"
Electronegativity refers to the fact that oxygen tends to attract electrons toward itself more than other atoms (such as hydrogen in the case of an H2O molecule)
TRUE or FALSE: the subcomponents of biological molecules and their sequence have little effect toward the properties of the moleule
FALSE: the properties of biological molecules refer heavily on the sequnces.T
TRUE or FALSE: the properties of water result from its nonpolarity
FALSE: the properties of water come from its polarity
What is a prime example of a polar covalently bonded molecule?
H2O
How are hydrogen bonds different from other types of bonds?
Hydrogen bonds are different from other types of bonds because they are between a hydrogen atom and another atom with a slightly negative charge. This causes the bond to be very weak and easily breakable, but when there are many hydrogen bonds at once, they can create a strong force (ex. Surface tension).
How does the density of frozen water help the marine life?
It allows marine life to live underneath the floating ice sheets.
How does the high specific heat of water help the climate?
It moderates the temperatures of large bodies of water. Water absorbs heat during the day and release it during the night.
What is an example of how water acts as a universal solvent?
NaCl dissolving in water
What types of covalent bonds are there?
Nonpolar bonds and polar bonds
What is an example of a solution?
Salt mixed with water
How does electronegativity affect the interactions between water molecules?
Since oxygen is more electronegative than hydrogen, it pulls the electrons towards itself in H2O, resulting in the oxygen being slightly negative and the hydrogen being slightly positive. This allows the water molecules to easily break apart and form hydrogen bonds with each other quickly. The hydrogen atoms are pulled towards the available oxygen atoms, and the oxygen atoms are attracted to the available hydrogen atoms.
What is an example of how evaporative cooling helps maintain homeostasis in humans?
Sweating
TRUE or FALSE: living systems depend on the properties of water that result from its polarity and hydrogen bonding
TRUE
TRUE or FALSE: the hydrogen bonds between water molecules result in cohesion, adhesion, and surface tension
TRUE
What is an example of the polarity of water?
Water being a universal solvent (because the oxygen attracts to positive atoms and the hydrogen attract to negative atoms)
What is an example of cohesion?
Water being able to stay connected during capillary action
What is an example of capillary action?
Water going against gravity in a plant stem to go towards the leaves.
What is an example of surface tension?
Water strider walking on water
When does an ionic bond form?
When there is a TRANSFER of electrons from one to another atom, forming ions.
What type of bond connects the hydrogen atoms to the oxygen?
covalent bonds