About base

No, the definitio of a base is a subtance will react with acid to produce salt and water as the ONLY PRODUCT.(neutonization)

acid + base = salt + water

sodium carboate react with acid will form carbon dioxide, water and salt. Which WATER and SALT is not the only product.

Na2CO3 + 2HCl(a e.g of acid)= 2NaCl + CO2 + H2O

Therefore, sodium carboate is not a base.

hope it can help u
In conclusion, base is the substance which has neutronization reaction with acid, a neutronization is a reaction between acid and base which will have salt and water as the only product. Moreover, alkali is soluble base.

2007-04-13 18:39:23 補充：
although Na2CO3 is not a base.....but it has alkali property, it is because it will also give out some OH- ions in water(AL level)CO3 2- H2O HCO3 - OH- .