Strong Acid Strong Base Titrations (Simplified): Study with Video Lessons, Practice Problems & Examples

Strong acid-strong base titrations involve stoichiometric calculations of neutralization reactions, where moles of acid and base react in a defined ratio. For example, hydrochloric acid (HCl) reacts with barium hydroxide (Ba(OH)₂) to produce barium chloride (BaCl₂) and water. The process typically starts with known molarity and volume, allowing for the determination of unknown quantities through mole-to-mole comparisons using coefficients from the balanced equation. This method is essential for understanding acid-base interactions and calculating concentrations in titrations.

Strong Acid Strong Base Titrations (Simplified) Concept 1

Now realize that when we talk about strong acid-strong base titrations, they deal with stoichiometric calculations of chemical reactions involving neutralizations between strong acids and bases. We're going to say, what is neutralization now? Neutralization is where we have a chemical reaction in which the moles of acid and base react stoichiometrically to one another. What's important here in these types of titration or neutralization reactions is that strong acids neutralize bases. It doesn't matter if the bases are weak or strong. That's what they do in general. And strong bases neutralize acids in general. Again, it doesn't matter if they're weak or strong. In this case, we're focusing on strong acids and strong bases playing off of one another. Okay? We're not going to talk about weak acids or weak bases being involved here. That's for a later discussion. So just realize that when we're talking about a strong acid, strong base titration, all it really is is stoichiometry of acids and bases.

Strong Acid Strong Base Titrations (Simplified) Concept 2

So remember, strong acid, strong base titrations are just stoichiometric questions dealing with acids and bases. Because of that, we can use a stoichiometric chart. Now remember, the chart uses the given quantity of an acid or base in this case to determine the unknown quantity of another acid or base. Here we have HCl, so hydrochloric acid, reacting with barium hydroxide to produce barium chloride and water. We're given this volume and molarity of barium hydroxide, we're given this volume of HCl, and you're looking for the missing molarity. Realize here that looking at this equation from a stoichiometric viewpoint tells us that our given amount that we start with is usually in molarity, or it can be given to us in grams, or it can be given to us in moles. Now, the molarity is usually coupled with volume. So it's usually liters per molarity, which leads us directly into moles of given. And remember, just like the other stoichiometric charts we've seen, once you know your moles of given, you would do the jump. Where are you going to go from moles of given to moles of unknown? And during this jump, you have to look do a mole to mole comparison, which means you have to use the coefficients in the balanced equation. Once you have your moles of unknown, you can go anywhere you want. You can use that to find the molarity of the unknown, or you can even use it to find the grams of unknown. So if you've seen my videos on stoichiometric charts before, this is kind of like a rehash, but now looking and focusing through the lens of an acid and a base undergoing a titration. Now that we've gone over the basic parts of it that we've seen before in earlier videos, move on to the next video and let's take a look at the example question.

Strong Acid Strong Base Titrations (Simplified) Example 1

So here it says, if it takes 25.13 ml of 0.320 molar barium hydroxide to titrate 31 ml of a solution containing hydrochloric acid, what is the molar concentration of hydrochloric acid? Alright. So to solve this, we're going to do the following steps. First, we're going to convert the given quantity into moles of given. Our given quantity is this part here. It's volume of molarity. Think of this as a complete set. "Of" means multiply, and remember that moles equals liters times molarity. So, if I change these milliliters into liters and multiply them by the molarity, that'll give me the moles of barium hydroxide. Alright. So what I'm going to do first is I'm going to have 0.02513 liters. I converted it into liters already. Remember that the molarity means moles over liters, so that's 0.320 moles of barium hydroxide per 1 liter. Liters cancel out, and what I've just done is found the moles of given, the moles of barium hydroxide.

Now step 2 says to do a mole to mole comparison to convert moles of given into moles of unknown. Alright. So we look at the balanced equation. We put moles of barium hydroxide here on the bottom so it can cancel out, and moles of hydrochloric acid here on top. According to my balanced equation, for every one mole of barium hydroxide, we have 2 moles of hydrochloric acid. So these moles cancel out. Now at this point, this will give me the moles of hydrochloric acid, which are 0.0160832 moles.

Next, it says, if necessary, convert the moles of unknown into the desired units. We have to go a step further; we have to find molarity. So, if the molarity is required, then divide the moles of unknown by its liters. So I just found the moles of my unknown, but that's not my molarity, that's not my molar concentration. I'm going to take those moles that I just found and then divide it by its liters. HCl has 31 ml's, which when you convert to liters is 0.031 liters. Here, that'll give me my molarity as 0.519 molar HCl. So this would be my final answer for this particular question.

How many grams of HNO₃ are required to completely neutralize 110.0 mL of 0.770 M LiOH?

• A. 0.0847 g
• B. 57.0 g
• C. 84.7 g
• D. 5.34 g

What is the molar mass of a 0.350 g sample of a HA acid if it requires 50.0 mL of 0.440 M Sr(OH)₂ to completely neutralize it? A is used as a place holder for the unknown nonmetal of the acid.

• A. 15.9 g/mol
• B. 31.8 g/mol
• C. 5.30 g/mol
• D. 7.95 g/mol

Here’s what students ask on this topic:

What is a strong acid-strong base titration?

A strong acid-strong base titration is a type of chemical analysis used to determine the concentration of an unknown acid or base. It involves a neutralization reaction where a strong acid reacts with a strong base in a stoichiometric ratio. For example, hydrochloric acid (HCl) can react with barium hydroxide (Ba(OH)₂) to produce barium chloride (BaCl₂) and water (H₂O). The process typically starts with known quantities of one reactant, allowing for the calculation of the unknown concentration through mole-to-mole comparisons using the balanced chemical equation.

How do you calculate the unknown concentration in a strong acid-strong base titration?

To calculate the unknown concentration in a strong acid-strong base titration, follow these steps: 1) Write the balanced chemical equation for the reaction. 2) Determine the moles of the known reactant using its molarity and volume. 3) Use the stoichiometric coefficients from the balanced equation to find the moles of the unknown reactant. 4) Calculate the molarity of the unknown reactant by dividing the moles of the unknown by its volume in liters. This method relies on the stoichiometric relationship between the acid and base.

What is the role of the stoichiometric chart in strong acid-strong base titrations?

The stoichiometric chart is a tool used to simplify calculations in strong acid-strong base titrations. It helps in converting given quantities (such as molarity and volume) into moles, and then using the balanced chemical equation to find the moles of the unknown reactant. The chart guides you through the process of mole-to-mole comparisons and allows you to determine the unknown concentration or mass of the reactant. It is particularly useful for visualizing the steps involved in the titration process.

Why is it important to use a balanced chemical equation in titration calculations?

Using a balanced chemical equation in titration calculations is crucial because it ensures that the stoichiometric relationship between the reactants is accurately represented. The coefficients in the balanced equation indicate the mole ratio of the acid to the base, which is essential for determining the moles of the unknown reactant. Without a balanced equation, the calculations would be incorrect, leading to inaccurate results. The balanced equation provides the foundation for all stoichiometric calculations in the titration process.

Can strong acids neutralize weak bases in titrations?

Yes, strong acids can neutralize weak bases in titrations. The principle of neutralization applies regardless of the strength of the base. However, in the context of strong acid-strong base titrations, the focus is on reactions where both the acid and base are strong. The calculations and stoichiometric relationships are similar, but the pH changes and endpoint detection might differ when dealing with weak bases. For strong acid-strong base titrations, the reaction goes to completion, making the calculations straightforward.