About 10ml of concentrated HCl was transferred to a 1-L volumetric flash and diluted to mark with distilled water. When this solution was used to titrate a sample of pure sodium carbonate, Na2Co3, weighing 0.3054 gram, it took 35.09 ml to reach the methyl red end point. The reaction is given by:

Question

About 10ml of concentrated HCl was transferred to a 1-L volumetric flash and diluted to mark with distilled water. When this solution was used to titrate a sample of pure sodium carbonate, Na2Co3, weighing 0.3054 gram, it took 35.09 ml to reach the methyl red end point. The reaction is given by:

2HCl + Na2CO3 --> H2CO3 + 2NaCl

Answer 1

I forgot:

What is the concentration of the solution?

Answer 2

2HCl + Na2CO3 ==> 2NaCl + H2O + CO2

mols Na2CO3 = grams/molar mass = estimated 0.0029
mols HCl = mols Na2CO3 x (2 mol HCl/1 mol Na2CO3) = approx 0.0029 x 2/1 = approx 0.0058 mols HCl
M HCl = mols HCl/L HCl. You know mols HCl and L HCl (0.03509 from the problem), solve for M HCl.

Answer 3

Is molarity also called the concentration of the solution? I got 0.1641 M HCl. Thank you for your help!

Answer 4

There are several units for concentration. One is molarity, but there is also molality, normality, % by mass, % by volume, % by weight/volume and others. Usually titrations are done and the concn is reported in molarity which is mols/L solution.

Answer 5

To calculate the molarity of the HCl solution, we need to use the equation and the given information.

First, let's find the number of moles of sodium carbonate (Na2CO3) in the given sample.
We know the weight of the sample is 0.3054 grams, and the molar mass of Na2CO3 is 106 g/mol.

Number of moles of Na2CO3 = mass / molar mass
= 0.3054 g / 106 g/mol

Now, we need to determine the number of moles of HCl that react with the sodium carbonate. According to the balanced equation, 2 moles of HCl react with 1 mole of Na2CO3.

Number of moles of HCl = 2 * moles of Na2CO3

Now, let's find the volume of the HCl solution that reacts with the sodium carbonate sample. We know that it took 35.09 mL of the HCl solution to reach the end point of the reaction.

Now, we can calculate the molarity (M) of the HCl solution using the formula:

Molarity (M) = moles of HCl / volume of HCl solution (in liters)

First, let's convert the volume from milliliters (mL) to liters (L):

Volume of HCl solution = 35.09 mL / 1000 mL/L

Finally, we can calculate the molarity of the HCl solution by dividing the moles of HCl by the volume of the HCl solution:

Molarity of HCl solution = moles of HCl / volume of HCl solution

Plug in the values for the moles of HCl and the volume of the HCl solution to get the final answer.