The electron pair is attracted so close to the chlorine atom that they are practically transferred to the chlorine atom (an ionic bond).
ðɪ ᵻlˈɛktɹɑːn pˈɛɹ ɪz ɐtɹˈæktᵻd sˌoʊ klˈoʊs tə ðə klˈoːɹiːn ˈæɾəm ðæt ðeɪ ɑːɹ pɹˈæktɪkli tɹænsfˈɜːd tə ðə klˈoːɹiːn ˈæɾəm ɐn aɪˈɑːnɪk bˈɑːnd.