How many milliliters of EDTA solution containing 150 mg and 175 mg per mL should be used in prep

How many milliliters of EDTA solution containing 150 mg and...

Key Concepts

Concentration and Unit Conversion

This concept involves understanding how to express and convert the amount of a solute in a solution. Specifically, it requires converting between mass units (such as milligrams and grams) and connecting these values with volume, which is crucial when determining how much of a concentrated solution to mix in order to achieve a target concentration.

Percentage Concentration

Percentage concentration, often expressed as a weight/volume percentage in solutions, represents the mass of solute (in grams) present per 100 mL of solution. Interpreting a 16% solution means recognizing that there are 16 grams of EDTA in every 100 mL, and this percentage is used to calculate the total mass of solute required for the final solution volume.

Solution Preparation from Multiple Stock Concentrations

When preparing a solution from stock solutions of different concentrations, it is essential to understand how each stock's concentration contributes to the final mixture. This involves calculating the required volume from each stock based on its concentration and the overall target concentration, ensuring the final mixture contains the precise amount of solute needed.

Dilution and Mixture Calculations

These calculations involve determining the volume of a stock solution of known concentration that must be added to a given volume of diluent to achieve a desired final concentration. This process often requires setting up an equation based on the conservation of solute mass, ensuring that the total amount of solute from the stock solution equals the amount needed in the final diluted solution.

Transcript

00:01 So we're given an acid -based titration, and we know it's an acid -based titration because we have an acid and a base, and we're giving concentrations one known volume and one unknown volume, as the basis of titration.

00:12 And we're trying to figure out the missing volume of the base.

00:16 So what the first thing you should always do is complete the equation.

00:19 So acid and base will give you water, and your salt, which would be barium nitrate.

00:27 So it's metal and the non -metal.

00:31 The barium is plus two, the nitrate is minus one.

00:33 When they cross, it will look like this.

00:36 And then you balance.

00:37 I need two nitrates, so i'm gonna put a two right here.

00:40 And then the trick is if you have to balance either or, the water will also have to be balanced, so you put the same coefficient.

00:47 Because water is h -o -h, right? so if i have two hydroxides here and two hydrogens here, i will need two hydrogens here.

00:56 So that's another way that you can balance.

00:59 But when you're doing titrations, you can just, if one of those has to be balanced, then you have to do the same to the water.