Page 52 - Chemistry ICSE Class X

40 ICSE Chemistry – 10
contribute one electron each to share one pair of electrons between them.
This leads to the formation of a single covalent bond between the two
hydrogen atoms. ThKU KU KNNWUVTCVGF DGNQY

Chlorine molecule (Cl )
2
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atom has seven valence electrons. Thus, each Cl atom requires one more
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chlorine atoms achieve this by mutually sharing one pair of electrons as
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Oxygen molecule (O )
2
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6JG GNGEVTQPKE EQPſIWTCVKQP QH QZ[IGP KU ( ) . Each oxygen atom has six
,
26
electrons in its outermost shell. Thus, it requires 2 more electrons to achieve
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Nitrogen molecule (N )
2
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,
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FQPG D[ OWVWCNN[ UJCTKPI VJTGG RCKTU QH GNGEVTQPU CU UJQYP DGNQY

Water molecule (H O)
2
Water molecule contains two hydrogen atoms and one oxygen atom. The
eNGEVTQPKE EQPſIWTCVKQP QH J[FTQIGP KU () and of oxygen is ( ) . Thus,
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,
1
26
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electron each and oxygen atom needs two electrons.
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