Sorry DrBob, it's me again!
Here's the info:
Antacid Brand: Life
Concentration of HCl: 0.1845 M
Concentration of NaOH: 0.1482 M
Trial 1:
1.Mass of Table: 1.2173g
2.Volume of HCl added: 75.0 mL
3.Milliomoles of HCl added:(0.1845M x 75.0mL= 13.84 mmoles
4.Volume of NaOH used: 17.14 mL
5.Millimoles of NaOH used in titration: (0.1482M x 75.0mL= 11.12 mmoles
6.Millimoles of HCl that did not react with the antacid: (0.1482M x 14.18mL NaOH= 2.504 mmoles)
7.mmoles of HCl neutralized by tablet:(13.84 HCl-2.504 NaOH = 11.34 mmoles)
8.mmoles of H+ neutralized per gram of antacid:(7/1.2173=5.750 mmoles/g)
I used you work to fix my problems but I had a few questions. For #6, where'd you get the 14.18mL? and For #8, where'd you get the 7 from.
and...if I were asked to find the average in mmoles of H+/g of antacid tablet, how would I do that?
Sorry, my brain isn't functioning at its best.
sorry, i posted twice but I don't understand where the 7 came from in #8.
The 7 stands for step #7. You were to use the number you had in step 7 and divide that by mass antacid tablet to arrive at the value for step 8.
No problem at all! Let's go through your questions:
For #6, the value of 14.18 mL is the volume of NaOH used in the titration, as mentioned in step 4. It corresponds to the volume required to neutralize the excess HCl that did not react with the antacid. In this case, it was determined to be 17.14 mL in Trial 1.
For #8, the value of 7 is obtained from step 3, where you calculated the millimoles of HCl added using the concentration and volume of HCl. In Trial 1, it was found to be 13.84 millimoles of HCl.
To find the average in millimoles / gram (mmoles/g) of H+ for the antacid tablet, you would need to perform multiple trials and then calculate the average. If you have data from multiple trials, simply add up the millimoles of H+ neutralized for each trial and divide by the total mass of antacid used in all trials. Here's the general formula:
Average mmoles/g of H+ = (Total mmoles of H+ neutralized) / (Total mass of antacid used)
Remember to sum up the total millimoles of H+ neutralized and the total mass of antacid used from all the trials before calculating the average.
I hope that helps! Let me know if you have any more questions.