Final answer:
Sodium bicarbonate is used in titration as a weak base to neutralize acids, which helps quantify the acid in a solution. By using stoichiometry and indicators like bromothymol blue, we can determine when the neutralization is complete and calculate the amount of baking soda added.
Step-by-step explanation:
We use sodium bicarbonate in titration because it can act as a weak base to neutralize an acid, which is important for determining the amount of acid present in a solution. In a titration where sodium bicarbonate is used alongside a stronger base such as NaOH, we can solve for the amount of acid that NaOH neutralizes. The remaining moles of acid correspond to the number of moles of sodium bicarbonate added. Sodium bicarbonate, also known as baking soda, is commonly used in cooking, while its counterpart sodium carbonate (washing soda) is utilized for maintaining acid balance in foods and boosting detergent efficiency in laundry.
To illustrate with an example, if we are titrating a 0.25 M solution of HNO3 with 0.15 M NaOH and we want to find out how many grams of sodium bicarbonate were originally added to the solution, we first need to calculate the moles of NaOH used in the titration. This is done by multiplying the volume of NaOH solution used by its molarity. The resulting moles of NaOH are equal to the moles of HNO3 neutralized. If there is excess HNO3, it means that the initial sodium bicarbonate was less than the excess amount of acid. Stoichiometry and titration techniques allow us to calculate this value. The color change of an appropriate indicator, like bromothymol blue, or using a pH meter indicates the equivalence point where the reaction is complete.