Chapter 3/4

adhesion

when different types of molecules stick together

aqueous solution

solutions with water as a solvent

cohesion

when the same type of molecules stick together

density of ice

• less dense as a solid than liquid, which is why it floats

• water temp decreases = molecules slow down, h-bonds help stabilize

• acts as buffer during winter

evaporative cooling

• “sweating”

• happens when h-bonds are formed/broken

• regulates temperature as highest-energy water molecules leave the surface as water vapor

hydrophilic

• polar

• really small

• do dissolve

hydrophobic

• non-polar

• really big, do not dissolve

kinetic energy

energy of motion

thermal energy

form of kinetic energy linked to random movement of atoms/molecules

solute

substance being dissolved

solvent

substance that does the dissolving

specific heat

energy required to inc. temp

surface tension

skin like surface on top of liquid caused by molecules tightly sticking together

• more commonly seen on lakes cuz water molecules stick together

solution

final mixed substance

acid

• pH < 7

• increase H+

base

• pH > 7

• decrease H+, increase OH

buffer

prevents pH from changing

hydronium ion

• H₃O⁺

• water molecule with an extra hydrogen ion attached

• forms when: acid is dissolved in water

• more hydronium ions = more acidic

hydroxide ion

• OH⁻

• strong base

hydrogen ion

• H⁺

• strong acid

carbon

• are in organic compounds

  • each carbon atom can form 4 covalent bonds

hydrocarbon

organic compounds that have long chains of carbon + hydrogen

functional group

common group of bonded atoms

• changes chemical property of the molecule that it’s attached to

  • reactivity, polarity, acidity

• replaces 1 or more H

isomers

have same formula but different arrangement of atoms

organic compound

have carbon in them

• each carbon atom can make 4 covalent bonds