Module 12

Question 1

Oxidation State

Answer 1

The difference btwn # of valence elections when atom’s unbonded and # of valence electrons atom controls in compound

Question 2

Positive oxidation state

Answer 2

The # of electrons an atom loses when bonded
Ex) Max positive oxidation state for F: +7
(IF atoms were able to bond with all 7 electrons)

Question 3

Negative oxidation state

Answer 3

The # of electrons an atom gains when bonded
Ex) Max negative oxidation state for H: -1
(H only able to gain 1 more electron to complete shell)

Question 4

How to find amt of excess reactant

Answer 4

Subtract from theoretical yield (calc if don’t have) the mass of the other reactant

Question 5

finding theoretical yield

Answer 5

use this:
amt of actual yield/amt of theoretical yield = % of actual / % of theoretical yield
OR
adding masses reactants

Question 6

moles-to-moles limiting reactant problems

Answer 6

good luck, lol

jk, just make sure that if something affects one mole, that there’s still enough of the other reactant so that it’s not a limiting reactant

Can find out w/ this:
n mol A consumed * ( mol B / mol A ratio^) = x mol B consumed

if there’s enough of the other reactant given in the problem, then it’s a green light

^this order is important; don’t mess it up

Question 7

Predicting products of a reaction (single-replacement)

Answer 7

1. Find products
2. Check for signs (use solubility rules if needed)
3. If something comes out with negative or positive, might have to double it and the rest of the eqn to cancel it out.

Question 8

Finding percent yield, given actual amt

Answer 8

1.find mol of reactants consumed
2. get mol ratio (mol products / mol reactant) to find mol products
3. multiply molar mass of product w/ moles to get mass
4. take given actual amt then divide w/ product mass

Question 9

Reaction Sequence Stoichiometry

Answer 9

1. Find net reaction
2. Find net yield (multiply the % yields of each step, then by 100 to get % net yield)
3. Convert the moles needed from given mass
4. Find 100% yield of moles Cu produced by multiplying moles needed by mole ratio
5. Divide by net yield to find actual moles
6. Convert moles to mass

Question 10

Gravimetric Reaction

Answer 10

analytical technique based on measurement of mass