It's Okay to Be Smart6 Chemical Reactions That Changed History Season 3 Episode 39 | 7m 18s From fire to food, check out these life-altering reactions that surround us everyday. Aired: 04/03/17 Rating: NR Closed CaptioningVideo has closed captioning.checkmarkAdd to WatchlistProblems Playing Video?Report a ProblemClosed CaptioningShare:Share this video on FacebookFacebookShare this video on TwitterTwitterShare this video on Google PlusGoogleShare this video via EmailE-mailEmbedEmbed Code for this videoEmbed CodeIt's Okay to Be Smart6 Chemical Reactions That Changed HistorySeason 3 Episode 39Width in pixels px Height in pixels px Copied to your clipboardLabelCopy to ClipboardClick to copy embed code for videoCloseCloseReport a ProblemBefore you submit an error, please consult our Troubleshooting Guide.Type of ErrorVideo doesn't loadVideo loads, but doesn't playVideo jumps back/forwardOnly audio is streamingSponsorship playback errorOtherPlease add more detailsCancelSubmit ReportYour report has been successfully submitted. Thank you for helping us improve PBS Video.CloseCloseClose