The electron dot structure for each molecule are:
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a. H:O:O:H
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The partial negative charges are on the Oxygen atoms.
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b. H:Cl:
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The partial negative charge is on the Chlorine atom.
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c. H:Br:
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The partial negative sign is on Bromine atom.
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d. H:O:H
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The partial negative sign is on the Oxygen atom.
