when you titrate the base solution to the phenolphthalein end level you have caried out the next reaction: Na2CO3 + HCl = NaHCO3 + NaCl
You have responded exactly 50 percent the Na2CO3. The remaining solution then provides the unreacted NaHCO3 from this response plus the unreacted NaHCO3 at first in the solution. Solution mixture of reaction (1) at the assent point is usually alkaline http://au.answers.yahoo.com/question/index?qid=20100826232153AAwADLC the answer is in how Na2CO3 responds with stomach acids. its a two stage equation.
Na2CO3 + HCl --> NaHCO3 + NaCl
NaHCO3 +HCl --> LASER + H2O + NaCl
according to this mechanism, almost no carbon dioxide is if you added HCl dropwise into a expensive of Na2CO3. this is because the small amount of HCl might only take the carbonate to the end of the first response. it would consider additional HCl to start producing the gas from the second reaction, which explains why you only start to see bubbles on the end of the titration. the second reaction starts off when you cannot find any Na2CO3 still left.
however if you titrated the carbonate into acid, a number of drops of carbonate is going to meet alot of acid HCl. the carbonate completes the first effect quickly and starts to produce gas in the second effect almost instantly. so you see bubbles immediately and over the whole titration. http://uk.answers.yahoo.com/question/index?qid=20061022105208AAlMpqW Neutralization reaction among Na2CO3 and HCl acid takes place into two steps- Na2CO3+ 2HCl => NaHCO3+ 2NaCl
NaHCO3+HCl => NaCl & H2CO3
The ultimate reaction,
Na2CO3+ 2HCl => 2NaCl + H2CO3
Inside the first step, the perfect solution is is standard due to the formation of a salt where the simple part is usually stronger than the acidic component (NaHCO3). So , in order to determine the equivalent stage of this reaction Phenolphthalein is utilized. As the salt that forms due to the neutralization reaction, produces more OH-, so the solution becomes a simple one and...