Unit 1 Flashcards
Empirical Formula
Find masses
Look up give Ar values
Divide masses by Ar
Find ratio
Avogadro’s Number
6.022 x 10^23
% Element
ram x no of atoms / maximum mass of product x100
Rate of Reaction
product formed / time taken
Relative Mass and Charge
proton: 1 +1
neutron: 1 0
electron: 0 -1
Moles of Solute in a Solution
moles= concentration x volume
mol dm-3 = mol/dm3
dm-3 = 1000cm3
concentration: mol dm-3
volume: cm3
Moles in a Gas
moles= volume/24
Shapes of Molecules
Electron pairs repel Lone pairs repel more bonding pairs lone pairs name angle
Oxidation
The loss of electrons
Reduction
Gain of electrons
Oxidation Number
If it was ion, the charge is the same as the oxidation number.
Acids
Release H+ ions in aqueous solution Proton donor HCl hydrochloric H2SO4 sulfuric HNO3 nitric
Base
Neutralise acids
Proton acceptor
Soluble base that releases OH- ions in aqueous solution
Salt
A salt is formed when the H+ ion of an acid is replaced by a metal ion or ammonium ion
Neutralisation reaction
Acid + base –> salt + water
Acid + carbonate –> salt + water + CO2
Water of Crystalisation
Water molecules that form an essential part of the crystalline structure of a compound
Water of Crystallisation Moles
Calculate amount in moles of anhydrous
Then moles of water
Ratio to determine formula
Sub Shells
S- 2 electrons
P- 6 electrons
D- 10 electrons
F- 14 electrons