The thermite reaction, Fe₂O₃ + Al → Al₂O₃ + Fe produces so much heat that the Fe product melts. This reaction is used industrially to weld metal parts under water, where a torch cannot be employed. It is also a favorite chemical demonstration in the lecture hall (on a small scale). (b) Calculate how many grams of aluminum are needed to completely react with 500.0 g of Fe₂O₃ in this reaction.

Video transcript

Hey everyone. So here we're given an unbalanced reaction. They were asked to determine the mass of Cobalt three sulfate as required to completely react With 78.6 g. Austronesian sulfide. You have S. R. S. The C. O two sl four three. And it's going to be able to ask Art S. 04, C. 02 S. Three. They have strong. You go for how about an oxygen on both sides. Here we have one strontium or sulfur to cobalt. In 12, oxygen here we have one strontium or sulfur to cobalt. And for oxygen Since we have 12 optional and reacting side and four on the product side Most part three over here get 12 three in front Australian sulfate. So now we have three strontium over here And six sulfur over here. If you put a three in front of strontium sulfide, we're gonna have three strong um over here. six sulfur over here and now this is balanced. Now we need to convert from grams Australian so fine. two g. Of course about three. No faith. I have 78.6 g Australian so fine. And in one mall Australian self I have the Mueller mass. And this is 87. Plus 32.066. Which is 1 19 0.7. And we have three moles Australian sulfide in the reaction in one month of Kobach three. So fate in the reaction someone. One more Of course about three sulfate. We have the Mueller mass. And this is to I'm 58 . plus three times 32 .06. past 12. I'm 15 . And this gave us 406 0.1 g. Would you give us 88 0.9 g? Thanks for watching my video. And I hope it was helpful.