Chemistry XI Unit 7

Oxidation is:

loss of electrons gain of electrons loss of hydrogen loss of oxygen

Reduction is:

loss of electrons gain of electrons loss of oxygen formation of acids

Redox reaction involves:

only oxidation only reduction both oxidation and reduction no electron transfer

Oxidation number of element in elemental form:

always +2 always 0 always +1 varies

Oxidation number of oxygen in compounds:

always -2 always -1 always 0 -2 except in peroxides (-1)

Oxidation number of hydrogen in compounds:

always +1 always -1 always 0 +1 except in hydrides (-1)

In monatomic ion, oxidation number equals:

atomic number charge on ion mass number proton number

Sum of oxidation numbers in compound:

equals zero equals charge of compound positive always negative always

In KMnO₄, oxidation state of Mn is:

+ 2 + 7 + 5

In Cu²⁺, oxidation state is:

+ 2 + 1 - 2

Oxidation number change indicates:

bonds formed electron transfer bonds broken no change

The substance that loses electrons in redox:

oxidizing agent reducing agent catalyst spectator

The substance that gains electrons in redox:

oxidizing agent reducing agent catalyst spectator

In oxidation-reduction, if one substance oxidized:

another reduces nothing else happens temperature increases pressure decreases

Balanced redox equations must have:

equal atoms equal charge on each side equal mass and charge same number of molecules

Half-reaction method separates:

oxidation and reduction into separate equations atoms and molecules acids and bases elements and compounds

In acidic solution, O is balanced using:

H₂O OH⁻ H₂O and H⁺ O₂

In basic solution, H is balanced using:

H⁺ H₂O OH⁻ H₂O and OH⁻

Electrode potential measures:

tendency to gain electrons current in circuit resistance in cell number of electrons

Standard electrode potential (E°)measured vs:

Al reference Ag reference SHE (Standard Hydrogen Electrode) Cu reference

In electrochemical cell:

reactions occur non-spontaneously ΔG > 0 always ΔG = -nFE° ΔG = nFE°

In galvanic (voltaic) cell:

spontaneous reactions occur non-spontaneous reactions forced electrolysis occurs reactions require current

In electrolytic cell:

spontaneous reactions occur electrical energy forces non-spontaneous reaction generates current produces electricity

Anode in electrochemistry:

where oxidation occurs where reduction occurs where circuit connects neutral electrode

Cathode in electrochemistry:

where oxidation occurs where reduction occurs positive terminal neutral electrode

In galvanic cell, anode is:

positive terminal negative terminal where current enters neutral

In galvanic cell, cathode is:

negative terminal positive terminal where current leaves neutral

Faraday's Law relates:

current to voltage amount of substance to charge speed to force energy to mass

In electrolysis: Q =

I × V I × T V / R P / I

Nernst equation calculates:

cell potential at non-standard conditions standard cell potential equilibrium constant electrode resistance

FILLBLANK:_____ is loss of electrons.

Oxidation Reduction Ionization Deposition

FILLBLANK:_____ is gain of electrons.

Reduction Oxidation Sublimation Combustion

FILLBLANK:Hydrogen has oxidation state _____ (usually).

positive one (or +1) negative one zero positive two

FILLBLANK:In monatomic ion, oxidation number = _____

charge of ion atomic mass atomic number electron count

FILLBLANK:In acidic solution, oxygen balanced with _____

H₂O and H⁺ H₂O and OH⁻ OH⁻ only H⁺ only

FILLBLANK:_____ is where oxidation occurs.

Anode Cathode Electrode Separator

FILLBLANK:_____ is where reduction occurs.

Cathode

FILLBLANK:_____ relates amount of substance to charge.

Faraday's Law

FILLBLANK:Cell potential: E_cell = E°(_) - E°(_)

cathode, anode

TRUE/FALSE: Oxidation is loss of electrons.

TRUE FALSE

TRUE/FALSE: Reduction is loss of electrons.

TRUE FALSE

TRUE/FALSE: Oxidizing agent is oxidized.

TRUE FALSE

TRUE/FALSE: Reducing agent is reduced.

TRUE FALSE

TRUE/FALSE: Free element has oxidation state 0.

TRUE FALSE

TRUE/FALSE: Oxygen always has oxidation state -2.

TRUE FALSE

TRUE/FALSE: Monatomic ion oxidation number equals ion charge.

TRUE FALSE

TRUE/FALSE: Galvanic cells require external power.

TRUE FALSE

TRUE/FALSE: In galvanic cell, anode is negative.

TRUE FALSE

TRUE/FALSE: In electrolytic cell, cathode is positive.

TRUE FALSE

TRUE/FALSE: More positive electrode potential means better oxidizing agent.

TRUE FALSE

TRUE/FALSE: Electrolysis is spontaneous process.

TRUE FALSE