Chapter Three Flashcards
Water is polar; what does that mean?
oxygen is more electronegative than hydrogen (oxygen pulls electrons closer to itself)
What is a hydrophilic molecule?
a water-loving molecule; polar, dissolves and bonds with water
What is a hydrophobic molecule?
a water-fearing molecule; nonpolar, does not dissolve or bond with water
What are water’s emergent properties?
- cohesive and adhesive behaviors
- it can moderate temperature
- expands when frozen
- versatile solvent
What is cohesion?
attraction to self (hydrogen bonds)
What is adhesion?
attraction to other polar molecules
What is surface tension?
how easy or difficult it is to stretch or break the surface of a liquid; water has high surface tension
What is thermal energy?
the total kinetic energy of matter; depends on matter’s volume
What is temperature?
the average kinetic energy of molecule in a substance regardless of volume
What is heat?
the transfer of thermal energy from one body of matter to another
Why does water expand when solidified?
hydrogen bonding
Ice floats on liquid water; why is this important
it insulates and keeps bodies of water from completely freezing
What is pH?
the negative logarithmic measure of hydrogen ion concentration
pH is measured on a scale from ___ to ___
0 to 14
Acids have a pH _______ than 7
less
