Why are the standard solution always prepared in a volumetric flask?

Standard solutions are prepared in volumetric flasks because they are more accurate than a beaker.

Why do you think a volumetric flask is used to prepare standard solutions rather than a beaker or graduated cylinder?

Pipets and volumetric flasks are used when we need to know a solution’s exact concentration; graduated cylinders, beakers, and/or reagent bottles suffice when a concentrations need only be approximate.

What should be done to the volumetric flask before using it to prepare a solution?

Clean a volumetric flask before use. Rinse the flask several times with the solvent that will be used to prepare the solution. Inspect the flask to ensure that it is clean. Grease or other contaminants may cause the water to bead on the inside surface of the flask.

How do you maintain a volumetric flask?

Cleaning Pipets and Volumetric Flasks

1. Clean pipets and volumetric flasks using warm soapy water.
2. Rinse with tap water followed by three to four rinses with deionized water. This water rinse should form a smooth sheet when poured through clean glassware.
3. Dry using acetone to remove water.

How does a volumetric flask work?

A volumetric flask is lab glass or plasticware used to prepare a solution. It is used to make up a solution to a known volume. Volumetric flasks are used to measure volumes much more precisely than beakers or Erlenmeyer flasks.

Why use a volumetric flask over a graduated cylinder?

A volumetric flask should be used whenever an accurate concentration of solution is required. Graduated Cylinders are volumetric measuring devices designed to measure and deliver accurate volumes of liquids.

When using a volumetric flask How close should the meniscus be to the line for maximum precision?

The meniscus must be read consistently at arm’s length. Parallax error is the apparent displacement of an object as seen from two different viewpoints that are not in line with the object.

Does volumetric flask have to be dry?

Proper Use of Volumetric Glassware. In this course you will use three types of precision calibrated glassware: burets, pipets and flasks. This type of calibrated glassware is usually referred to as volumetric glassware. Thus, you must never dry any volumetric glassware in a drying oven.

When using a volumetric flask Why do we have to fill it exactly on the given mark?

A volumetric flask has a large round bottom with only one graduation mark positioned on the long narrow neck. The position of the mark facilitates the accurate and precise reading of the meniscus.

What is a volumetric flask used for?

A volumetric flask is used when it is necessary to know both precisely and accurately the volume of the solution that is being prepared. Like volumetric pipets, volumetric flasks come in different sizes, depending on the volume of the solution being prepared.

Can volumetric flasks be heated?

Do not heat volumetric glassware (it will break if you do). Usually you can get around the problem of wet volumetric glassware by rinsing it with 4 or 5 small aliquots of the solution to be measured so the solution replaces the water. Beakers are roughly graduated and may be used for estimating the volume of a liquid.

How is a volumetric flask used to prepare a solution with a known concentration?

Fill the volumetric flask about halfway with distilled water or deionized water (aqueous solutions) or other solvent. Transfer the solid to the volumetric flask. Rinse the weighing dish with the water to make certain all of the solute is tranferred into the flask. Stir the solution until the solute is dissolved.

How do you prepare a solution with a volumetric flask?

Preparation of a Standard Solution with a Volumetric Flask A volumetric flask is used to prepare a solution of definite concentration. First, add an appropriate amount of distilled water to the beaker containing the solid sample precisely weighed. Dissolve the sample completely using a stirring stick.

How do you dissolve a solid sample in a flask?

Dissolve the sample completely using a stirring stick. And, transfer the entire liquid from the beaker into the flask. In order to transfer the entire solution in the beaker as well as on the stirring stick, wash them well with distilled water. Next, transfer the rinsed liquid to the flask.

What happens when you mix two different liquids in a flask?

When two different liquids are mixed, a volume change may occur, therefore, don’t add distilled water at once up to the marked line. While adding distilled water in small quantities a little below the marked line, gently shake the flask to homogenize the solution. First, move your eyes to the level of the marked line of the flask.

How do you prepare the solution of a solid sample?

First, add an appropriate amount of distilled water to the beaker containing the solid sample precisely weighed. Dissolve the sample completely using a stirring stick. And, transfer the entire liquid from the beaker into the flask.