I am suppose to calculate the theoretical amount (volume) of 3M sodium hydroxide needed to convert 1.5 g of benzoic acid to its salt.
Also calculate the volume of 12M HCl needed to convert the sodium benzoate back to benzoic acid.
how do I go about doing this?
Thanks
It's a stoichiometry problem. Actually, two of them. I'll do the first and leave the second for you. By the way, the lasrt one I worked almost completely for you BECAUSE I wanted to print it out (with the solution) and put in a notebook I keep. I think benzoic acid is
C6H5COOH + NaOH ==> C6H5COONa + HOH
Convert 1.5 g benzoic acid to moles.
moles = grams/molar mass.
Using the coefficients in the balanced equation, convert moles benzoic acid to moles of NaOH.(It's 1:1)
Now convert moles NaOH to volume.
M = moles/L. You know moles and M, calculate L.
For the second part, you're going the other way BUT you already now how many moles benzoic acid you started with. The moles of the salt will be the same thing. You can go directly to the last step and convert 12 M HCl to volume needed.
I'm doing the same thing but I do not understand it fully. All of my general chemistry knowledge is gone.
Well, if you want to convert 1.5 grams of benzoic acid to its salt, you'll need to react it with sodium hydroxide. The first step is to calculate the number of moles of benzoic acid you have. Since the molar mass of benzoic acid is about 122.12 g/mol, you have:
1.5 g / 122.12 g/mol = 0.0123 mol
Since the balanced equation tells us that one mole of benzoic acid reacts with one mole of sodium hydroxide, you'll need an equal number of moles of sodium hydroxide. So, you'll also need 0.0123 moles of sodium hydroxide.
Now, to find the volume of 3M sodium hydroxide needed, you'll use the number of moles and the molarity of the solution. Molarity is given by the formula:
Molarity = Moles of solute / Volume of solution (in liters)
Rearranging the formula, you can solve for the volume of solution:
Volume of solution (in liters) = Moles of solute / Molarity
So, plugging in the values:
Volume of solution (in liters) = 0.0123 mol / 3M = 0.0041 L
Converting this to milliliters (ml), you get:
Volume of solution (in ml) = 0.0041 L * 1000 ml/L = 4.1 ml
So, you'll need about 4.1 ml of 3M sodium hydroxide to convert 1.5 g of benzoic acid to its salt.
Now, to calculate the volume of 12M HCl needed to convert the sodium benzoate back to benzoic acid. Since the balanced equation tells us that one mole of sodium benzoate reacts with two moles of hydrochloric acid, we'll need twice the number of moles of sodium benzoate to react with the hydrochloric acid.
Since you started with 0.0123 moles of sodium benzoate, you'll need:
2 * 0.0123 mol = 0.0246 mol of hydrochloric acid
Now, using the same formula as before:
Volume of solution (in liters) = Moles of solute / Molarity
You can find the volume of 12M HCl:
Volume of solution (in liters) = 0.0246 mol / 12M = 0.0021 L
Converting this to milliliters:
Volume of solution (in ml) = 0.0021 L * 1000 ml/L = 2.1 ml
So, you'll need about 2.1 ml of 12M HCl to convert the sodium benzoate back to benzoic acid.
Hope that helps! And remember, science is all about balancing equations, just like balancing on a tightrope.
To calculate the theoretical amount (volume) of 3M sodium hydroxide needed to convert 1.5 g of benzoic acid to its salt, you need to use the stoichiometry of the balanced equation for the reaction between benzoic acid (C6H5COOH) and sodium hydroxide (NaOH).
The balanced equation is as follows:
C6H5COOH + NaOH -> C6H5COONa + H2O
From the equation, you can see that the mole ratio between benzoic acid and sodium hydroxide is 1:1. This means that for every mole of benzoic acid, you will need one mole of sodium hydroxide.
To find the number of moles of benzoic acid, you divide the given mass by the molar mass of benzoic acid. The molar mass of benzoic acid is 122.12 g/mol.
Number of moles of benzoic acid = Mass of benzoic acid / Molar mass of benzoic acid
= 1.5 g / 122.12 g/mol
≈ 0.0123 moles
Since the mole ratio between benzoic acid and sodium hydroxide is 1:1, you will need 0.0123 moles of sodium hydroxide.
Now, to calculate the volume of 3M sodium hydroxide needed, you can use the equation:
Volume (in liters) = Number of moles / Concentration
Volume of 3M sodium hydroxide needed = 0.0123 moles / 3 mol/L
≈ 0.0041 L or 4.1 mL
Therefore, the theoretical amount of 3M sodium hydroxide needed to convert 1.5 g of benzoic acid to its salt is approximately 4.1 mL.
Now, to calculate the volume of 12M HCl needed to convert the sodium benzoate back to benzoic acid, you will use the same stoichiometry. The balanced equation for the reaction between sodium benzoate (C6H5COONa) and HCl (hydrochloric acid) is:
C6H5COONa + HCl -> C6H5COOH + NaCl
From the equation, you can see that the mole ratio between sodium benzoate and HCl is 1:1.
Since you know the number of moles of benzoic acid used (0.0123 moles), you will need an equal number of moles of HCl. Therefore, the volume of 12M HCl needed can be calculated as:
Volume (in liters) = Number of moles / Concentration
Volume of 12M HCl needed = 0.0123 moles / 12 mol/L
≈ 0.001 L or 1 mL
Therefore, the theoretical amount of 12M HCl needed to convert the sodium benzoate back to benzoic acid is approximately 1 mL.
Please note that these calculations assume ideal conditions and do not take into account any losses or inefficiencies during the reaction.
To calculate the theoretical amount of 3M sodium hydroxide needed to convert 1.5 g of benzoic acid to its salt, you need to follow these steps:
1. Determine the molar mass of benzoic acid:
- The molar mass can be obtained by adding up the atomic masses of all the elements in the compound. In this case, benzoic acid has the formula C6H5COOH, so you can find the molar mass using a periodic table.
2. Calculate the number of moles of benzoic acid:
- Divide the given mass of benzoic acid (1.5 g) by its molar mass to obtain the number of moles.
3. Use the balanced chemical equation:
- The reaction between benzoic acid and sodium hydroxide can be represented as follows:
C6H5COOH + NaOH → C6H5COONa + H2O
- From the balanced equation, you can see that one mole of benzoic acid reacts with one mole of sodium hydroxide to produce one mole of sodium benzoate.
4. Calculate the volume of 3M sodium hydroxide required:
- Since you know the number of moles of benzoic acid, it is equal to the number of moles of sodium hydroxide needed for the reaction.
- Use the formula: Moles = Molarity × Volume (in liters)
Rearrange the formula to solve for volume:
Volume = Moles / Molarity
- Substitute the values into the formula using the known molarity of 3M sodium hydroxide.
To calculate the volume of 12M hydrochloric acid (HCl) needed to convert the sodium benzoate back to benzoic acid, follow these steps:
1. Use the balanced chemical equation:
- The reaction between sodium benzoate and hydrochloric acid can be represented as follows:
C6H5COONa + HCl → C6H5COOH + NaCl
- From the balanced equation, you can see that one mole of sodium benzoate reacts with one mole of hydrochloric acid to produce one mole of benzoic acid.
2. Calculate the number of moles of sodium benzoate:
- Since you already resolved the number of moles of benzoic acid, it is equal to the number of moles of sodium benzoate.
3. Determine the number of moles of hydrochloric acid:
- The number of moles of hydrochloric acid will be the same as the number of moles of sodium benzoate, as per the balanced chemical equation.
4. Calculate the volume of 12M hydrochloric acid required:
- The formula to calculate volume is the same as explained above but using the known molarity of 12M hydrochloric acid.
Please note that these calculations assume 100% efficiency and do not take into account any other reactants present or dilution factors.