here in this example, question and says, predict whether a reaction occurs and write the balanced molecular equation. So here we have sodium carbonate reacting with hydroponic acid. Alright, so Step one, we're going to break up reacting one and reacting to into their ionic forms. Sodium carbonate is composed of sodium ion. It's a group one A. So it's plus one and carbonate ion, which is a poly atomic ion. So it's 03 to minus. Hydroponic acid is composed of H plus ion h plus one, bro mean is in group seven A. So it's minus one Step two. We swap Ionic partners by remembering that opposite charges attract. So we're gonna apply the rules that we've learned when it comes to creating new compounds from their ionic forms. If we take a look, this positive and this negative are attracted to one another, so they're going to combine and remember when your numbers and your charges are the same, the two ions just combined together and the charges disappear. So this will give us an A B R plus. Then we have here the numbers and the charges were different. When they're different, they don't just disappear and combine. They crisscross The two from here comes here, and the one from here comes here. That would give us at this point H two CO three. Now remember, are soluble ity rules and a B R N A. Is a group one a ion. Anything connected to a group on a I on his acquis insoluble. And then look, we made hte to see 03 That is one of our median product. So Step three says, identify the median product or gas that forms from the gas evolution equation except for hydrogen sulfide, break it up into water and gas. So here we have carbonic acid, which we know will break down further into water, which it will be a liquid plus CO two gas. So you do you do not keep the carbonic acid there. It completely breaks down to give me those two pieces and step four Last step says, If necessary, balance your molecular equation by placing the correct coefficients in front of each molecule. So here we just have to see isn't balanced. We have here to sodium, and here we only have one, so I'd put a two in front of this C So we have one carbon and three oxygen's. We have one carbon to oxygen's three oxygen. So there goes the CO three there. Hydrogen is We have one hydrogen here and one br here. But on the product side, we have to be ours because the two gets distributed to the BR and two hydrogen. It's so we have to put a two here. Now our equation is balanced, so these would be all the coefficients for this balanced gas evolution equation.