q1.
The label on an antacid remedy states that each tablet contains 750 mg of aluminum hydroxide. Calculate the volume of stomach acid, 0.10 mol/L HCl(aq), which can be nuetralized by one antacid tablet.
Q2.
Compare equivalence point to endpoint
q1.
The label on an antacid remedy states that each tablet contains 750 mg of aluminum hydroxide. Calculate the volume of stomach acid, 0.10 mol/L HCl(aq), which can be nuetralized by one antacid tablet.
Al(OH)3 + 3HCl ==? 3H2O + AlCl3
The remainder of this problem is worked the same as the NaOH/H2SO4 problem I solve for you in your last post. Don't forget to change 750 mg to g and I assume you know mols = g/molar mass.
Q2.
Compare equivalence point to endpoint
The equivalence point is the point (in an acid/base titration) where what we are titrating is the same as the titrant being added (best described in terms of number of equivalents of one equal to number of equivalents of the other but equivalents and normality are not being taught at many schools now, much to my sorrow). The end point is the point at which an indicator TELLS us we have reached that point; hence the name end point. We try to pick indicators that have an end point that is the same as the equivalence point but usually that can't be done. However, with the judicious choice of indicators, we can usually keep the titration error to a very small number. There are equivalence points for other titrations as well as acid/base; the only difference is that we aren't measuring pH.
I hope this helps.
To answer q1, you need to use the balanced chemical equation for the reaction between aluminum hydroxide (Al(OH)3) and hydrochloric acid (HCl). The equation is:
Al(OH)3 + 3HCl → 3H2O + AlCl3
From the equation, you can see that one mole of aluminum hydroxide reacts with three moles of hydrochloric acid to form three moles of water and one mole of aluminum chloride.
To calculate the volume of stomach acid that can be neutralized by one antacid tablet containing 750 mg (or 0.75 g) of aluminum hydroxide, you first need to convert the mass of aluminum hydroxide to moles.
The molar mass of aluminum hydroxide (Al(OH)3) is 78 g/mol. Therefore:
moles of Al(OH)3 = mass of Al(OH)3 / molar mass of Al(OH)3
= 0.75 g / 78 g/mol
Now that you have the moles of aluminum hydroxide, you can determine how many moles of hydrochloric acid will be required to react with it.
Since the balanced equation shows that one mole of aluminum hydroxide reacts with three moles of hydrochloric acid, you can multiply the moles of aluminum hydroxide by the stoichiometric ratio to get the moles of hydrochloric acid.
moles of HCl = moles of Al(OH)3 × (3 moles of HCl / 1 mole of Al(OH)3)
Finally, you can calculate the volume of hydrochloric acid using its molarity:
volume of HCl = moles of HCl / molarity of HCl
Given that the molarity of the stomach acid is 0.10 mol/L, you can substitute that value into the equation to find the volume of stomach acid:
volume of HCl = moles of HCl / 0.10 mol/L
That will give you the volume of stomach acid that can be neutralized by one antacid tablet.