Exam Three Study Cards Flashcards
(26 cards)
What are the two types of replacement reactions and what are their rules?
Metal Replacement and Halogen Replacement. For Metals, whoever is higher on the activity chart, for Halogens, whoever is more electro negative
How do you tell if double replacement reactions will go throguh?
The Solubility chart. At least one of the products must be insoluble.
What’s the tip Letterman gave for balancing reactions?
Do one element at a time, in rounds.
What is an oxidation/Combustion reaction?
A Hydrocarbon and oxygen heated -> Co2 and H2O
What should you do when balancing a reaction and one of the coefficients on one side is odd?
Multiply it by two.
What is the special moley number/
6.02 x 10^23
What is the relation between Moles, Weight and number of atoms?
1 mole = sum of attomic weights= 6.02 x 10^23 particles
How do you find mass percent?
Total mass of the elements atoms in the compound/total atomic mass.
What is an empirical formula?
The lowest ratio of the constituent elements. Example: C6H12O6 -> 1:2:1, had to be broken down, not empirical till it’s in ratio, making it CH2O
What is the process from turning mass percents into a formula?
- Convert the percents into grams
- Convert the grams into Moles
- Make a skeletal formula out of the moles
- Divide by the smallest mole
- Multiply away any .5 or .33 or .25 by multiplying by 2/3/4.
- Round any too close.
How do you turn an empirical formula into a molecular formula?
Find the Scale Factor. Scale factor is the Molar mass/empirical mass.
How do you find limiting reactants in a formula?
Make the bridge for both of your reactants. Weght1 to mole1, mole1 to mole2, mole2to weight2. You can reuse mole2 to weight2 for the secodn bridge
Triple the Reactants…?
Triple the reaction. Half the reactants, half the reactions. Reactions can read like ratios this way
What is Percent Yield/
Actual Yield/Theoretical Yield
What is Theoretical yield?
Yield of the limiting reactant.
What is electricity?
The flow of electrons.
What is Voltage?
The speed of electron flow
What is Current?
The amount of electrons being sent.
What is a “Redox” reaction?
A reaction where electrons move between elements. One element is “Reduced” and one is “oxidized”
What does it mean to oxidize a reactant?
The oxidized reactant loses electrons. Oxidized reactants are Reducing Agents by necessity.
What does it mean to reduce a reactant?
The reduced reactant gains electrons. Reduced reactants are Oxidizing agents by necessity.
Are Oxidiation Numbers the same as ionic charge numbers?
Only in single elements.
What are the rules with compounds and Oxidiation numbers?
Alkali metals are always +1, Earth metals are always +2. Oxygen is always -2, Fluorine is always -1. Hydrogen is contrarian, and is -1 with metals and +1 with nonmetals. The sum of Oxidization Numbers in a compound is it’s charge.
What is a half reaction?
The reaction of either oxidization or reduction, on it’s own, removed from the full reaction. Be sure to add electrons on the side that needs it.
