Dear Student
Elements have their own propertyto make them differ from other when elements join chemically to form a compound the compounds property is different from other. Atom in molecule can be joined by covalent or ionic bond. Ionic compound form when atoms transferred their electron from one another to get the stable structure. Which atom give electron it become positive charge on the other hand which atom take the charge it become negative charge. Covalent bond form by mutual sharing of electron of atom.
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