Lesson 1 Flashcards
A naturally occurring substance with a varied chemical composition.
mineral
this is where most metals come from
mineral
Bold
A mineral deposit concentrated enough to allow the economical recovery of a desired metal.
ore
is a deposit in Earth’s crust of one
or more valuable minerals.
ore
8 is a deposit in Earth’s crust of one
or more valuable minerals.
Aluminum, iron, calcium, magnesium, sodium, potassium, titanium and manganese
is a rich source of some metal ions, such as Na+, Mg2+, and Ca2+
seawater
Italicized
Vast areas of the ocean
floor are covered with ____________ which are made up mostly of manganese, along
with iron, nickel, copper, and cobalt in a chemically combine state.
manganese nodules
________________ are
combinations of rock on the sea bottom which is composed of concentric layers of iron and manganese hydroxides around a core.
manganese nodules
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The science and technology of separating metals from their ores and of compounding alloys is called _____________.
metallurgical process
An _________ is a solid solution either of two or more metals, or of a metal or metals with one or more nonmetals.
alloy
The three principal steps in the
recovery of a metal from its ore are:
(1) _________ of the ore
(2) production of the _
______,
(3) _________ of the metal.
(1) preparation of the ore
(2) production of the metal,
(3) purification of the metal.
In ____________, the desired mineral is separated from waste materials that is
usually clay and silicate minerals.
ore prior treatment
Italicized
Waste materials that are usually clay and silicate minerals which are collectively called the _________
gangue
Italicize
In this process, the ore is finely ground and
added to water containing oil and detergent.
flotation
Flotation process:
In this process, the ore is finely ground and
added to water containing oil and ________. The liquid mixture is then beaten or blown to form a _______. The ____ preferentially wets the mineral particles, which are then carried to the ____ in the froth, while the _______ settles to the bottom. The froth is ______ off, allowed to collapse, and dried to _________ the mineral particles.
detergent
froth
oil
top
gangue
skimmed
recover
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____________ metals are strongly attracted to magnets.
Ferromagnetic
Another physical separation process makes use of the ______ properties of certain
minerals.
magnetic
The mineral ___________, in particular, can be separated from the gangue by using a strong electromagnet.
magnetite (Fe3O4)
__________ is another ferromagnetic metal.
Cobalt
__________ forms amalgams with a number of metals.
mercury
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An ______________ is an alloy of mercury with another metal or metals.
amalgam
Mercury can therefore be used to extract metal from
________. Mercury dissolves the silver and gold in an ore to form a liquid _________, which is easily
separated from the remaining ore. The gold or silver is recovered by distilling off _______.
ore
amalgam
mercury
Italicized
Because metals in their combined forms always have positive oxidation numbers, the production of a free metal is a ___________.
reduction process
Italicized
an ore may be _________ to drive off volatile impurities and at the same time to convert the carbonates and
sulfides to the corresponding oxides, which can be reduced more conveniently to yield the
pure metals.
roasted
Bold
Most major metallurgical processes
now in use involve ____________, procedures carried out at high temperatures.
pyrometallurgy
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_____________ is suitable for very electropositive metals, such as sodium, magnesium, and aluminum. The process is usually carried out on the anhydrous molten
oxide or halide of the metal.
Electrolytic reduction
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We can use a more electropositive metal as a reducing agent to separate a less electropositive metal from its compound at high temperatures.
Chemical Reduction
________ and ______ are predominantly suitable for the extraction of iron.
hematite
magnetite
The
metallurgical processing of iron involves the chemical reduction of the minerals by carbon
(in the form of coke) in a ___________.
blast furnace
italicize
A blast of hot air is forced up the furnace from the bottom, that’s why it is called a ______
blast furnace
italicize
A mixture of calcium silicate and calcium aluminate that remains molten at the furnace temperature is known as _______.
slag
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Iron ore, limestone,
and coke are introduced at the top of the
furnace. Iron is obtained from the ore by
reduction with carbon
blast furnace
italicize
Iron extracted in this way contains many impurities and is called __________; it may contain up to 5 percent carbon and some silicon, phosphorus, manganese, and sulfur.
pig iron
italicize
Pig iron is granular and brittle. It has a relatively low melting point (about 1180°C), so it can be cast in various forms; for this reason it is also called _______.
cast iron
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is an iron alloy that contains from 0.03 to 1.4 percent carbon plus various amounts of other elements.
steel
italicize
The conversion of iron to steel is essentially an __________ in which the unwanted impurities are removed from the iron by reaction with oxygen gas.
oxidation process
italicize
One of several
methods used in steelmaking is the __________.
basic oxygen process
bold
what process is this:
Molten iron from the blast furnace is poured
into an upright cylindrical vessel. Pressurized oxygen gas is introduced via a water-cooled
tube above the molten metal. Under these conditions, manganese, phosphorus, and silicon,
as well as excess carbon, react with oxygen to form oxides. These oxides are then reacted
with the appropriate fluxes (for example, CaO or SiO2) to form slag.
basic oxygen process
bold
The basic oxygen process of
steelmaking. The capacity of a typical
vessel is ____ tons of cast iron
100
If manganese is the main impurity, then an _________ such as
SiO2 is needed to form the slag:
acidic flux
The properties of steel depend not only on its chemical composition but also on the ________.
heat treatment
italicized
At high temperatures, iron and carbon in steel combine to form iron carbide, Fe3C, called _________.
cementite
When steel containing cementite is cooled slowly, the preceding
equilibrium shifts to the _______, and the carbon separates as small particles of graphite, which
give the steel a _____ color. (Very slow decomposition of cementite also takes place at room
temperature). If the steel is cooled ______, equilibrium is not attained and the carbon
remains largely in the form of cementite, Fe3C.
left
gray
rapidly
Steel containing cementite is ____ in color,
and it is harder and more ______ than that containing graphite.
light
brittle
italicized
Heating the steel to some appropriate temperature for a short time and then cooling
it rapidly in order to give it the desired mechanical properties is known as
tempering
In
this way, the ratio of carbon present as graphite and as cementite can be varied within rather
wide limits.
tempering
Three common purification procedures are
distillation, electrolysis, and zone refining.
Metals prepared by _____ usually need further treatment to remove impurities.
reduction
