3. malleable so they can be hammered into different shapes
4. ductile, so they can be drawn into thin wire
5. high in density. Of all the metals, lead is the highest in density
6. metals have high melting points and most are solids at room temperature
7. mercury is the only metal that is a liquid at room temperature
8. cesium and gallium have low melting points; (melting points are less than
30oC)
9. metals do not combine chemically with each other, but react with nonmetals
to form compounds
10. of all the metals, Group 1 (i.e. alkali metals) are the most reactive
11. metals near the center of the periodic table are less reactive
12. less reactive metals are more likely to be found in nature as uncombined
elements (i.e. copper, silver, gold)
13. reactive metals such as the alkali metals are never found as uncombined ele-
ments (i.e. lithium, sodium)
Many of the properties of metals, including large atomic radius, low ionization energy,
and low electronegativity, are due to the fact that the electrons in the valence shell of
a metal atoms can be removed easily. One characteristic of metals is their ability to
be deformed without breaking. Malleability is the ability of a metal to be hammered
into shapes. Ductility is the ability of a metal to be drawn into wire. Because the
valence electrons can move freely, metals are good heat conductors and electrical
conductors.
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Chemical Properties
Chemically, the metals differ from the nonmetals in that they form positive ions and
basic oxides and hydroxides. Upon exposure to moist air, a great many undergo cor-
rosion, i.e., enter into a chemical reaction; e.g., iron rusts when exposed to moist air,
the oxygen of the atmosphere uniting with the metal to form the oxide of the metal.
Aluminum and zinc do not appear to be affected, but in fact a thin coating of the
oxide is formed almost at once, stopping further action and appearing unnoticeable
because of its close resemblance to the metal. Tin, lead, and copper react slowly un-
der ordinary conditions. Silver is affected by compounds such as sulfur dioxide and
becomes tarnished when exposed to air containing them. The metals are combined
with nonmetals in their salts, as in carbides, carbonates, chlorides, nitrates, phosphates,
silicates, sulfides, and sulfates.
The Electromotive Series
( Kindly look up the series in any inorganic text and study it)
On the basis of their ability to be oxidized, i.e., lose electrons, metals can be arran-
ged in a list called the electromotive series, or replacement series. Metals toward
the beginning of the series, like cesium and lithium, are more readily oxidized than
those toward the end, like silver and gold. In general, a metal will replace any other
metal, or hydrogen, in a compound that it precedes in the series, and under ordinary
circumstances it will be replaced by any metal, or hydrogen, that it follows.
Non-Metals
The Properties of the nonmetals
1. nonmetals have low densities.
2. nonmetals are not ductile or malleable and brittle.
3. nonmetals are not lustrous and are dull.
4. nonmetals are poor conductors of heat and electricity except carbon in the
form of graphite.
5. nonmetals can be found in nature in the uncombined elemental form
6. fluorine is the most reactive of all the nonmetals.
7. nonmetals can combine with other nonmetals to form compounds such as:
carbon dioxide (CO ), carbon monoxide (CO), methane (CH ), and ammonia
2
4
(NH ).
3
Metalloids / semimetals
The Properties of the Semimetals
1. semimetals have both metallic and nonmetallic properties
2. semimetals are semiconductors, in other words, they are not as conducting as
metals and are not insulators like the nonmetals (i.e. silicon and gallium arsenide
(GaAs) are used widely in the semiconductor industry)
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Block elements
Alkali metals
The alkali metals are lithium, sodium, potassium, rubidium, cesium, and francium
(Li, Na, K, Rb, Cs, and Fr respectively). Hydrogen is often considered to be an alkali
metal (especially at low temperatures or high pressures), although some scientists
think of it as a nonmetal. The alkali metals are the elements located in Group IA (first
column) of the periodic table.
In many of its properties, lithium, exhibits the same characteristics as do the more
common alkali metals sodium and potassium; thus, the metal is highly reactive and
forms strong hydroxide solutions. In many respects lithium also shows similarities
to the elements of the alkaline-earth group, especially magnesium, which has similar
atomic and ionic radii.
Summary of Common Properties
1. Lower densities than other metals,
2. One loosely bound valence electrons
3. Largest atomic radii in their periods,
4. Low ionization energies,
5. Low electronegativities,