chem h last semiunit Flashcards
(22 cards)
Ways to speed up the dissolving process
Increase temp
Grind solute
Stir solute
Add catalyst
Dissolving process
The charges of the solvent are attracted to the solute’s opposite charges
Increase temp
There’s increased interaction with the solute thus increased kinetic energy of the solvent particles
Grind solute
The greater the surface area of the solid, the quicker the solvent can make contact with the solute
Stir solute
By stirring you move the solvent attached to the solute ion away from the surface allowing a fresh solvent particle to easily attach itself
Add catalyst
It allows the reaction to occur more quickly
Examples of catalysts
Sunlight, enzymes, chemicals
Example of an irreversible reaction
Combustion reaction
When does equilibrium occur ?
When the rate of reaction of one directions equals the other
Le Chatelier’s principle
If a system in equilibrium is disrupted then the system will shift to reestablish equilibrium
Ways to disrupt equilibrium
change in concentration, temp, pressure
Change in concentration
Adding consumes the substances, removing reproduces it
Change in pressure
Increase it, then it decreases
It decrease it, then increase it
Change in temp
Add heat, consume it
Remove heat, reproduce it
In a reversible reaction forward and reverse reactions happen,
In both directions at the same time
What is a redox reaction?
A reaction in which electrons are transferred
Oxidation
The process by which a substance loses 1+ electron
Reduction
The process by which a substance gains 1+ electrons
Reduction agent
Substance is oxidized
Oxidizing agent
Substance is reduced
Oxidation number
The number that represents the biding electrons
5 rules for oxidation numbers
- Neutral atom is 0
- Oxidation of any ion is its ionic charge
- Group 1A is +1, group 2A is +2, aluminum is always +3, F is always -1, hydrogen is +1, oxygen is -2
- The algebraic sum of the individual oxidation numbers in a neutral compound is 0
- same as above but with ions it’s the sum of the ionic charge
