Exam 3: Electrochemistry

Boron usually forms __ covalent bonds, which is contrary to the octet rule

three

Boron is found in boric acid which is used to __ and borax which is used _.

kill ants; as a detergent

Nitrogen can assume many oxidation states. What is the range?

-3 to +5

Nitrogen is found in __

explosives, fertilizers, and as an oxide in laughing gas, Viagra, smog, and preservatives.

Fertilizer is what? How is it made?

Ammonia is made with the Haber process from H₂ and N₂ at low temperatures with a catalyst.

Carbon has (how many) allotropes including C₆₀, which forms (what); graphite, which is (blank) hybridized; and diamond, which is (blank) hybridized

3; interesting tubular and spherical structures; sp²; sp³

__ is an inorganic form of carbon that is an essential part of a cycle involving the green house gas, (blank), a diprotic acid, and (blank)

CO₃^—; CO₂; limestone (CaCO₃)

__ is found in many common materials including soaps, toothpaste, fertilizer, and pesticides.

Phosphorous

__ is extracted from Ca₃(PO₄)₂ rock.

Phosphorous

__ is the backbone in nucleic acids like DNA

Phosphate

__ cause algae bloom and increasingly their use is discouraged for environmental reasons.

Phosphates

__ have small radii, high ionization energy, high electronegativity, and form -1 anions. Their oxides and hydrides are acidic.

Halides

__ inserts instead of OH^— in tooth enamel to protect from decay.

Fluroride.

Chlorine is manufactured as Cl₂, a strong [reducing/oxidizing] agent.

oxidizing

Chlorine is used in __ and _. It is also used to make (blank).

disinfection; sanitation; PVC tubing

Noble gases are (blank) with 2 or 8 electrons in filled shells. Specialty uses include as (blank), (blank) gases, and lights.

Claus and Contact processes combine to produce ___ through a series of [reduction/oxidation] and acid/base reactions.

H₂SO₄; oxidation

Sulfuric acid is the most manufactured chemical in the world. True or false?

True

The Claus process is a __-step [reduction/oxidation] process.

two-step; oxidation

The Claus process produces ___ from ___, which is a contaminant in natural gas, ___

elemental sulfur; H₂S; methane

The Contact process is a ___-step [reduction/oxidation] process.

four-step; oxidation

The contact process produces ___ from ___

H₂SO₄; elemental sulfur

About half of all sulfuric acid is used to ___ in rocks by (what method).

solubilize phosphate; the wet method

The wet method produces solubilized phosphate. What is it used for?

Fertilizers

Sulfuric acid is not just a strong acid. It is also a strong [reducing/oxidizing] agent and a strong ____ agent

oxidizing/dehydration

What is the lightest metal commonly used in commercial applications?

Aluminium

How is aluminum obtained? What process?

Bayer process - make aluminum oxide from bauxite rocks

Hall process - make aluminum from aluminum oxide

What is aluminum oxide used to form?

Ruby, sapphire, topaz gemstones

Alkali metals have [large/small] radii, [high/low] ionization energy, and [high/low] electronegativity.

large; low; low

Alkali metals form what kind of ions?

+1 cations

Alkali metals have [acidic/basic] oxides and hydrides.

basic

Do alkali metals react vigorously with water?

Yes

Do coinage metals react vigorously with water?

No

Examples of coinage metals?

Cu, Ag, Au, Pt

Beryllium forms __ bonds because of its relatively small size and ability to attract electrons.

covalent

Calcium is in building materials from ___ to ___

concrete; teeth

Mg⁺² in ___ makes the molecule [more/less] rigid to permit electron transport for photosynthesis instead of energy loss through vibrations

chlorophyll; less

Battery technology pushes boundaries by trying to make the [largest/smallest], least expensive, highest power, longest life, [reversible/irreversible] and environmentally safe battery

smallest; reversible

Secondary batteries are build with consideration given to [maximizing/minimizing] liquid or gas production so that contents of the reaction are better contained in the battery casing for __.

minimizing; recharging

Lithium-ion batteries have been known to ___ and are not allowed to [be transported in what way]?

catch fire; shipped as commercial cargo on planes

Parts of a Li-ion battery

Electrolyte; porous separator; lithium-carbon (graphite); lithium ion; lithium-metal oxide

Modern batteries are made with [solids/pastes or liquids/gases].

solids and pastes

Primary batteries are rechargeable. True or false?

False; secondary batteries are rechargeable and are the environmentally superior/more convenient choice.

What makes a battery inefficient?

Batteries that produce heat instead of work are inefficient.

Lightweight batteries use what kind of material? (density and charge density)

less dense; higher charge density

It is important to control heat dissipation for practicality and for safety. True or False?

True

Examples of famous primary batteries

• common alkaline batteries (Duracell)

• Zn-C

• Smaller specialty batteries like Zn-air batteries in hearing aids

Famous secondary battery examples

• Lithium-ion batteries in electronic and electric vehicles

• Lead-acid batteries in vehicles (gas-powered) that are recharged by an alternator when the engine is running

  • NIMH batteries that are a common household battery

Type and application of the alkaline battery

Primary; household

Type and application of the Zn-Hg, Zn-air battery

Primary; Hearing aids

Type and application of the Li-ion battery

Secondary; electronics/automobiles (electric)

Type and application of the Lead-acid battery

Secondary; automobiles (with an alternator)

Type and application of the NiCd battery

Secondary; household

Type and application of the NiMH battery

Secondary; household

How is rust made?

By oxidation of iron in the presence of both air and water for a long period of time

Rusting can be prevented by adding in metals that are [easier/harder] to oxidize than iron.

easier

How can you prevent rusting with Zn?

Galvanization of iron with Zn

How can you prevent rusting with Mg?

Use as a sacrificial electrode

How can you prevent rusting with Al?

Use as a sacrificial electrode

How can you prevent rusting with Cr and V?

Add stainless made of Cr and V to iron