by chance /baɪ ʧæns/ /baɪ ʧɑːns/
accidentally /ˌæk.sɪˈden.təl.i/ /ˌæksɪˈdɛntəli/
it just so happens that /ɪt dʒˈʌst sˌoʊ hˈæpənz ðˈæt/ /ɪt dʒˈʌst sˌəʊ hˈapənz ðˈat/