Question
Define : (i) Group (ii) Period.
✓
Answer
(i) Group : The vertical column of elements in the periodic table or elements is called a group.
(ii) Period : The horizontal row bf the elements in the periodic able of the elements is called a period.
(ii) Period : The horizontal row bf the elements in the periodic able of the elements is called a period.
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$
Fe _{( s )} \rightarrow Fe ^{2+}( aq )+2 e ^{-}
$
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2 Fe ^{3+}( aq )+4 H _2 O _{( l )} \rightarrow+\ldots \ldots \ldots+6 H ^{+}( aq )
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(Practice Activity Sheer -2 )
→The iron rust is formed due to reaction. Different regions on iron surface become anode and cathode.
Reaction on anode region:
$
Fe _{( s )} \rightarrow Fe ^{2+}( aq )+2 e ^{-}
$
Reaction on cathode region:
$
O _{2( g )}+4 H ^{+}( aq )+\ldots \ldots . .2 H _2 O _{( l )}
$
when $Fe ^{2+}$ ions migrate from anode region they react with.......to fomm $Fe ^{3+}$ ions.
A reddish coloured hytirated oxide is formed from. ions. It is called rust.
$
2 Fe ^{3+}( aq )+4 H _2 O _{( l )} \rightarrow+\ldots \ldots \ldots+6 H ^{+}( aq )
$
A way to prevent rusting..........
(Practice Activity Sheer -2 )
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