Second, the heat generated by the first part of the reaction often ignites the hydrogen gas, causing it to burn explosively into the surrounding air.
sˈɛkənd, ðə hˈiːt dʒˈɛnɚɹˌeɪɾᵻd baɪ ðə fˈɜːst pˈɑːɹt ʌvðə ɹɪˈækʃən ˈɔfən ɪɡnˈaɪts ðə hˈaɪdɹədʒən ɡˈæs, kˈɔːzɪŋ ɪt tə bˈɜːn ɛksplˈoʊsɪvli ˌɪntʊ ðə sɚɹˈaʊndɪŋ ˈɛɹ.