Page 18 - Chemistry ICSE Class X

6 ICSE Chemistry – 10
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ƚŽŵŝĐ ǀŽůƵŵĞ ĚĞĐƌĞĂƐĞƐ ŝŶ ŐŽŝŶŐ
ĨƌŽŵ ůĞŌ ƚŽ ƌŝŐŚƚ ŝŶ Ă ƉĞƌŝŽĚ ŽĨ ƚŚĞ Explanation: The number of protons and electrons in an atom
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Metallic Character

Metals are placed on the left hand side, in the middle and at the bottom of
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The elements that show a tendency to lose one or more electrons
and form positive ions (i.e., cations) are called metals.
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Na o Na + + e –
sodium metal sodium ion
(2,8,1) (2,8)
Mg o Mg 2+ + 2e –
magnesium magnesium ion
(2,8,2) (2,8)
On what factors does the metallic character of an element

depend
The metallic character of an element depends mainly upon the following
factors:

ƒ Atomic size. The greater the atomic size (or atomic radius) lesser is
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As a result, electrons can be removed more easily from the outermost
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metallic

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dŚĞ ĞůĞŵĞŶƚ ǁŚŝĐŚ ŚĂƐ Ă ŐƌĞĂƚĞƌ
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Thus, a metal having higher nuclear charge is less metallic

How does the metallic character vary in a group
Metallic character of elements in a group increases as we go down the
group 6JWU KP CP[ ITQWR VJG GNGOGPV YJKEJ CRRGCTU CV VJG bottom of the
group is the most metallic
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Explanation: Metallic character of an element is related to its electron-
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ŐƌŽƵƉ dŝŶ ;^ŶͿ Thus, cesium (Cs), is the most metallic and lithium (Li) is the least
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