Video narration
Shasher oxygen, khabarer lobone thaka chlorine ar beluner helium - era eki porjay saronite keno ache? Oxygen holo Group 16-er, loboner bhetorer chlorine Group 17-er, ar heliumer Group 18-er udahoron. Ekhon ashol sutro: tader bairer stor-er jojyota electron. Oxygen-er moto Group 16-e thake 6ti, tai purno stor pete sadharonoto 2ti electron nite ba bhag korte chay. Chlorine-er moto Group 17-e thake 7ti, tai aro 1ti pelei stor purno - era halogen. Heliomer bairer stor itimoddhei purno; tai Group 18-er gas, orthat nishkriyo gas, sadharonoto khub kom bikriya kore. Bujhle? Jinishgulo alada holeo niyom ektai: bairer electron-i acharon bole dey. Druto quiz! Sat-ti jojyota electron kon groupe? Group 17. Nishkriyo gas kon groupe? Group 18. Oxygen kon groupe? Group 16. Mone rakho: 16 - oxygen-dhoron, 17 - halogen, 18 - nishkriyo gas. Tahole shurute tin jinish eki saronite keno? Karon saroni ek, kintu bairer electron alada - tai group ar boishishtyo-o alada.