Table of Contents
- 1 What should you do if you fill the flask with water past the mark?
- 2 What is the possible error during preparation of a standard solution?
- 3 What glassware is used for dilution?
- 4 How do you minimize errors in titration?
- 5 How do you make a solution with a volumetric flask?
- 6 Why is it okay to reuse the same glassware for all the solutions above which step would you have to repeat each time if you used a new volumetric flask for each ratio?
- 7 Why do you use solution instead of water in a beaker?
- 8 Do you add too much solvent to a dilution?
What should you do if you fill the flask with water past the mark?
Overfilling the flask above the graduation mark ruins the volume measurement. In this case, the content inside the volumetric flask should be discarded. A pipette bulb should be used to withdraw and deliver liquids when using a pipette.
What is the possible error during preparation of a standard solution?
It can be either of end point error, misreading volumes, concentrations, faulty use of equipment, contaminated glass ware, etc. Some of errors are : Misjudging the color of the indicator near the end point – this is probably the most common one.
What do you do if you add a bit too much solvent when filling the volumetric flask?
If too much solvent is added, the solution must be discarded and a new solution should be prepared from the first step of the procedure.
Why don’t you fill up the volumetric up to the mark until all solid material is dissolved?
It is very difficult to dissolve the solid once the flask is filled to the mark, so make sure it is all dissolved before you fill to the mark. Stopper the flask tightly, invert it and shake to obtain a homogeneous solution.
What glassware is used for dilution?
A volumetric flask (measuring flask or graduated flask) is a piece of laboratory apparatus, a type of laboratory flask, calibrated to contain a precise volume at a certain temperature. Volumetric flasks are used for precise dilutions and preparation of standard solutions.
How do you minimize errors in titration?
Reducing uncertainties in a titration To reduce the uncertainty in a burette reading it is necessary to make the titre a larger volume. This could be done by: increasing the volume and concentration of the substance in the conical flask or by decreasing the concentration of the substance in the burette.
What are the safety precautions should follow when preparing standard solution?
Handling
- Never put solution transfer devices into the standard solution.
- Always pour an aliquot from the standard solution to a suitable container for the purpose of volumetric pipette solution transfer and do not add the aliquot removed back to the original standard solution container.
What do you do when you add a bit too much solvent?
If you add too much solvent, the solution may be too dilute for crystals to form. It is important to slowly cool the flask first to room temperature and then in ice-water. A rushed crystal formation will trap impurities within the crystal lattice.
How do you make a solution with a volumetric flask?
How to use a volumetric flask
- Add your solute to your solution.
- Add enough solvent to dissolve the solute.
- Keep adding your solvent until it gets close to the line marked on the volumetric flask.
- Use a pipette to fill the flask.
Why is it okay to reuse the same glassware for all the solutions above which step would you have to repeat each time if you used a new volumetric flask for each ratio?
It was okay to reuse the same glassware for all the solutions above because before each solution was made, the flask was prerinsed to remove the impurities and previous substance. – The purpose of prerinsing all glassware is to remove any impurities or leftover substances from the previous use of the glassware.
How do you shake a volumetric flask?
Manually: Stopper the flask with a glass or plastic stopper and shake the solution holding the flask with both hands. Never shake a volumetric flask while only holding the neck of the flask. Do not use your hand or finger to stopper the solution.
Do you add acid or water before adding aliquots?
It is therefore best to add all of the acid and most of the water to the volumetric flask or standard solution container (dilutions to weight) before adding the individual element concentrate aliquots. Mixing after each aliquot addition is strongly advised. When diluting to volume it is often found that the solution is above room temperature.
Why do you use solution instead of water in a beaker?
Rinsing with solution to be used ensures removal of any moisture adhering to glass. To deliver an accurate volume (aliquot) of solution from the beaker. Solution to be used. Rinsing with solvent, eg water, would dilute the solution so its concentration would no longer be known accurately.
Do you add too much solvent to a dilution?
Avoid This Common Dilution Mistake. It’s a common mistake to add too much solvent when making the dilution. Make sure you pour the concentrated solution into the flask and then dilute it to the volume mark. Do not, for example, mix 250 ml of concentrated solution with 1 liter of solvent to make a 1-liter solution.
How do you mark the liquid level in gas chromatography?
You can mark the liquid level after proceeding normally (dissolve and invert several times). With a help of a high quality volumetric syringe or gas tight syringe (e.g., 2.5 mL Hamilton used in gas chromatography injections) draw the excess liquid until the liquid level is back to the calibration line.