Can i please get a formula to calculate the concentration of an acid when it reacts with a standard solution? ( preferably 0.1 M NaOH and viniger )
Certainly! The concentration of an acid can be calculated using the concept of stoichiometry and the balanced chemical equation for the reaction.
First, let's write the balanced chemical equation for the reaction between an acid (Here, vinegar, which is mainly acetic acid, CH3COOH) and a standard solution of sodium hydroxide (NaOH):
CH3COOH + NaOH → CH3COONa + H2O
Now, the stoichiometry of the balanced chemical equation gives us the molar ratio between the acid and the base. In this case, it is 1:1, which means that one mole of acid reacts with one mole of base.
To calculate the concentration of the acid (CH3COOH), we need to know the volume of the standard NaOH solution (0.1 M) that reacted with a known volume of vinegar.
Let's say you took 25 mL (0.025 L) of vinegar and titrated it with 0.1 M NaOH solution until the reaction was complete. The volume of NaOH solution required to complete the reaction was 30 mL (0.03 L).
Now, we can use the equation:
Moles of CH3COOH = Moles of NaOH
To calculate moles of NaOH, we'll use the formula:
Moles = Concentration (M) × Volume (L)
Moles of NaOH = 0.1 M × 0.03 L = 0.003 moles
Since the balanced chemical equation tells us that the molar ratio between NaOH and CH3COOH is 1:1, the moles of CH3COOH is also 0.003 moles.
Finally, to calculate the concentration of the acid (CH3COOH), divide the moles of CH3COOH by the volume of vinegar used:
Concentration of CH3COOH = Moles of CH3COOH / Volume of vinegar used
Concentration of CH3COOH = 0.003 moles / 0.025 L = 0.12 M
Therefore, the concentration of acetic acid (CH3COOH) in your vinegar sample is approximately 0.12 M.