Chapter 2 Flashcards
Atomic mass unit
(amu) (u) (Dalton) (Da)
* It’s an extremely small mass we use to talk about atoms
* It’s equal to 1/12 of the mass of one 12C atom
* It’s equal to 1.6605 x 10−24 g
Molecular compounds have an average formula mass (or molecular mass)
It is equal to the sum of the average atomic masses of all its atoms
Ionic compounds also have an average formula mass (not molecular mass)
It is equal to the sum of the average atomic masses of all the atoms of its
formula
1 mole ( Avogadro’s number (NA) ) =
= 6.022 x 1023
The unit of molarity is
mol/L or M (molar)
PPM=
mass solute/mass solution ∗ 10^6 ppm
PPB=
mass solute/mass solution ∗ 10^9 ppm
Density is
the ratio of the mass of a substance to the volume occupied by that mass
All substances tend to expand or contract depending on the temperature
Therefore..
density depends on the temperature