When will a reaction occur?
Spontaneous (reaction)
Will occur without the input of energy
Is this an example of oxidation?: Mg ———> Mg + 2e-
Yes
Is this an example of reduction?: 2e- + 2H ———> H2
Yes
What is the first rule of assigning oxidation numbers?
the oxidation # of a free element is 0
A double replacement reaction will occur if one of the products is...
A precipitate (consult table F), water (neutralization), a gas
If H2CO3 is one of the products, then...
A reaction will occur because H2CO3 spontaneously decomposes into H2O (l) and CO2 (g)
What type of reaction is this and will it occur?: Pb(NO3)2 + 2KI ———> PbI2 (s) + 2KNO3 (aq)
Double Replacement; yes, a precipitate was formed
In single replacement reactions, a more active metal will....
Replace a less active metal (consult Table J)
A more active nonmetal will...
Replace a less active nonmetal
Particle Diagrams...
Show correct phase of matter + conservation of mass
Types of Redox Reactions:
Synthesis, decomposition, single replacement, combustion
Will this reaction occur?: Na2CO3 + HCl ———> NaCl + H2CO3
Yes, H2CO3 decomposes into H2O (l) and CO2 (g)
Will a reaction occur?: Mg + Zn(NO3)3 ———> Mg(NO3)2 + Zn
Yes, magnesium is above zinc in Table J
What is the second rule of assigning oxidation numbers?
the oxidation # of elements in compounds are found in the Periodic Table
What is the third rule of assigning oxidation numbers?
the oxidation # of hydrogen is +1 (except when combined with metals in metal hydrides - LiH)
What is the fourth rule of assigning oxidation numbers?
the oxidation of oxygen is -2 (except in peroxides H2O2 and Na2O2 and in OF2)
What is the fifth rule of assigning oxidation numbers?
the sum of the oxidation #s in a compound must equal 0
What is the sixth rule of assigning oxidation numbers?
the sum of the oxidation #s in a polyatomic ion must equal the charge of the ion
Oxidation Reduction Reactions (Redox)...
Involve the transfer of electrons, and the oxidation numbers of elements change
Group 1 is...
Always soluble
Reduction
An atom or ion gains electrons; oxidation number is reduced
Oxidation
An atom or ion loses electrons; oxidation number increases
Will a reaction occur?: Mn + Na
No, metals never react with metals
In order to replace H+....
A metal must be above H2
The H2 listed in Table J represents a...
Hydrogen ion (H+) in an acid
LEO says GER
Lose Electrons Oxidation, Gain Electrons Reduction