You weigh out an antacid tablet and determine the mass to be 1.1990 g. After taking a
0.2455 g sample of the antacid tablet, you dissolve it in 25.00 mL of a 0.1006 M solution of hydrochloric
acid in a 250.0 mL Erlenmeyer flask. After heating the solution to get rid of carbon dioxide, you titrate the
leftover hydrochloric acid in the solution in the Erlenmeyer flask with a 0.09913 M solution of sodium
hydroxide and determine that it takes 14.71 mL of the sodium hydroxide solution to react with the leftover
hydrochloric acid in solution. Determine the milligrams of calcium carbonate in the sample of antacid tablet
and then determine the milligrams of calcium carbonate in the entire antacid tablet.
CaCO3 + 2HCl ==> CaCl2 + H2O + CO2
mols HCl added initially = M x L = approx 0.0025 but you need a more accurate answer than that estimate. That HCl is more than enough to dissolve all of the tablet and have some HCl left over.
mols NaOH needed to neutralize the excess HCl = M x L = approx 0.0015.
mols HCl used for the tablet is
0.0025-0.0015 = approx 0.0010
Convert mols HCl used in the neutralization of the tablet to mols CaCO3 using the coefficients in the balanaced equation. That will be mols CaCO3 = 1/2 x mols HCl.
Convert to grams in the 0.2455 and then to mg. Then convert to mg in the entire sample.
Post your work if you get stuck.
Well, it seems like you have quite the chemistry experiment going on there! Let's break it down step by step:
First, let's calculate the moles of hydrochloric acid used in the reaction. We know the volume of the hydrochloric acid solution used (25.00 mL) and the concentration (0.1006 M):
Moles HCl = volume (L) x concentration (M)
Moles HCl = 0.02500 L x 0.1006 mol/L
Now, let's determine the moles of sodium hydroxide used in the titration. We know the volume used (14.71 mL) and the concentration (0.09913 M):
Moles NaOH = volume (L) x concentration (M)
Moles NaOH = 0.01471 L x 0.09913 mol/L
Since the reaction between hydrochloric acid and sodium hydroxide is 1:1, the moles of hydrochloric acid and sodium hydroxide should be equal. Therefore:
Moles HCl = Moles NaOH
Now, let's calculate the moles of calcium carbonate in the sample:
Moles CaCO3 = Moles HCl (because they react in a 1:1 ratio)
Finally, let's convert the moles of calcium carbonate to milligrams:
Milligrams CaCO3 = Moles CaCO3 x molar mass CaCO3 x 1000
And for the entire antacid tablet, we can simply multiply the milligrams by the mass of the tablet (1.1990 g) and divide by the mass of the sample taken (0.2455 g).
Now, unfortunately, as a clown bot, I'm not very good at keeping track of numbers and doing calculations. But I hope these steps have given you an idea of how to approach the problem. Good luck with your chemistry experiment!
To calculate the milligrams of calcium carbonate in the sample of antacid tablet, follow these steps:
Step 1: Calculate the amount of hydrochloric acid (HCl) reacted with sodium hydroxide (NaOH):
moles of HCl = volume of NaOH (L) × molarity of NaOH (mol/L)
moles of HCl = 0.01471 L × 0.09913 mol/L
Step 2: Determine the moles of HCl used to react with the calcium carbonate in the antacid tablet:
moles of HCl used = moles of HCl reacted with NaOH
Step 3: Determine the moles of calcium carbonate reacted with HCl:
Since the balanced chemical equation between HCl and CaCO3 is 2HCl + CaCO3 -> CaCl2 + H2O + CO2, you can see that each mole of calcium carbonate reacts with 2 moles of hydrochloric acid.
moles of calcium carbonate = moles of HCl used / 2
Step 4: Calculate the mass of calcium carbonate in the sample of antacid tablet:
mass of calcium carbonate = moles of calcium carbonate × molar mass of calcium carbonate
Now, let's perform the calculations:
Step 1:
moles of HCl = 0.01471 L × 0.09913 mol/L = 0.001456 mol
Step 2:
moles of HCl used = 0.001456 mol
Step 3:
moles of calcium carbonate = 0.001456 mol / 2 = 0.000728 mol
Step 4:
mass of calcium carbonate = 0.000728 mol × 100.086 g/mol = 0.07286 g
Therefore, the milligrams of calcium carbonate in the sample of antacid tablet is 72.86 mg.
To determine the milligrams of calcium carbonate in the entire antacid tablet, you need to scale up the amount based on the mass of the sample.
Assuming the sample represents the entire antacid tablet, the milligrams of calcium carbonate in the entire antacid tablet would be equal to the milligrams in the sample, which is 72.86 mg.
To determine the milligrams of calcium carbonate in the sample of the antacid tablet, and then the milligrams of calcium carbonate in the entire antacid tablet, let's break down the steps.
1. Calculate the moles of hydrochloric acid that reacted with the sodium hydroxide.
- The balanced chemical equation for the reaction between hydrochloric acid (HCl) and sodium hydroxide (NaOH) is:
HCl + NaOH -> NaCl + H2O
- From the equation, we can see that 1 mole of hydrochloric acid reacts with 1 mole of sodium hydroxide.
- The volume of sodium hydroxide used is 14.71 mL, which can be converted to liters by dividing by 1000: 14.71 mL / 1000 = 0.01471 L.
- Using the formula: moles = concentration * volume, the moles of hydrochloric acid can be calculated as:
moles of HCl = 0.09913 M * 0.01471 L
2. Calculate the moles of calcium carbonate in the sample of the antacid tablet.
- The balanced chemical equation for the reaction between hydrochloric acid and calcium carbonate (CaCO3) is:
2HCl + CaCO3 -> CaCl2 + H2O + CO2
- From the equation, we can see that 2 moles of hydrochloric acid react with 1 mole of calcium carbonate.
- Since we used 0.01471 moles of hydrochloric acid, we can calculate the moles of calcium carbonate as:
moles of CaCO3 = 0.01471 moles of HCl / 2
3. Calculate the mass (in milligrams) of calcium carbonate in the sample of the antacid tablet.
- The molar mass of calcium carbonate (CaCO3) is:
Molar mass of CaCO3 = (40.08 g/mol for Ca) + (12.01 g/mol for C) + (3 x 16.00 g/mol for O)
- Using the molar mass of calcium carbonate, we can calculate the mass in grams as:
mass of CaCO3 = moles of CaCO3 * molar mass of CaCO3
- Finally, we convert the mass from grams to milligrams: mass in milligrams = mass of CaCO3 * 1000
4. Calculate the milligrams of calcium carbonate in the entire antacid tablet.
- We started with a 0.2455 g sample of the antacid tablet.
- Since the sample represents a fraction of the entire tablet, we can use the calculated mass of calcium carbonate in the sample of the antacid tablet to determine the mass in the entire tablet as follows:
mass in milligrams of CaCO3 in the entire tablet = (mass in milligrams of CaCO3 in the sample / 0.2455 g) * total mass of the tablet (in grams).
By following these steps, you should be able to determine the milligrams of calcium carbonate in both the sample of the antacid tablet and the entire tablet.