Wash Bottle

Quick Answer: A laboratory wash bottle is a bottle fitted with a delivery tube and jet, used to direct a fine stream of distilled water or another rinsing liquid onto glassware, precipitates or filter paper. It lets a chemist rinse exactly where needed without pouring.

Directing a Rinse Where It Is Needed

Quantitative work depends on rinsing. When a precipitate is transferred to a filter, the last particles clinging to the beaker must be washed across; when a solution is moved to a volumetric flask, the beaker and funnel are rinsed into it; and during a titration the walls of the conical flask are rinsed so that splashed titrant can react. A laboratory wash bottle does all of these with a thin jet that can be aimed and stopped at once.

Two designs are in use. The common modern form is a squeeze bottle of flexible plastic, usually polyethylene, where pressing the sides forces liquid up the tube. The older glass form is a flask with two tubes through its stopper, in which the user blows into one tube to drive liquid out of the other; blowing by mouth is discouraged today. The listing does not say which design or material is supplied, so confirm this when ordering.

Wash bottles are normally kept for one liquid each, most often distilled or deionised water, with separate, clearly labelled bottles for ethanol or propanone, since a jet of the wrong solvent can dissolve a product or ruin a precipitate.

Specifications

Applications

• Washing a precipitate such as barium sulfate or silver chloride on filter paper during gravimetric analysis
• Rinsing the walls of the titration flask and the tip of the burette near the end point
• Quantitative transfer of a solution from beaker to volumetric flask
• Rinsing electrodes, such as a pH electrode, between measurements

Care & Handling

• Label every wash bottle with its contents and fill it only with that liquid.
• Point the jet into the vessel and away from people; a squeeze bottle gripped hard can spray unexpectedly.
• Keep the jet tip clean and unblocked, since a partly blocked tip gives an erratic spray.
• Empty and refill water bottles regularly rather than topping them up, so the water stays clean.

Why Choose LabEquip

Every titration bench and gravimetric practical needs at least one wash bottle, so schools and colleges usually order them by the dozen. LabEquip lists this item in its chemistry lab equipment range; send the design, size and quantity you want through the contact page.

Frequently Asked Questions

Why use a wash bottle instead of pouring from a beaker?

A wash bottle gives a thin, aimable jet that uses very little liquid and can be stopped instantly. That control matters when rinsing a precipitate or making a solution up to volume, where excess liquid would spoil the result.

Should I use tap water or distilled water in a wash bottle?

Use distilled or deionised water for analytical work, because tap water contains dissolved ions such as chloride and calcium that can react with or contaminate the sample. Tap water is fine only for the first rinse of dirty glassware.

Can a wash bottle hold acetone or ethanol?

Yes, if the bottle material resists the solvent and the bottle is clearly labelled. Keep solvent wash bottles away from flames and hot plates, because the jet can spray flammable liquid.

How do I wash a precipitate on a filter paper?

Direct a gentle stream around the upper edge of the filter paper so the liquid runs down and carries the solid into the cone. Several small washings, each allowed to drain, remove impurities better than one large washing.

Why does my plastic wash bottle keep dripping?

Warmth makes the air and vapour inside expand and push liquid out of the jet, especially with volatile solvents. Keep the bottle away from heat, and briefly loosen the cap to release the pressure before use.

How often should the wash bottle be cleaned?

Empty and rinse it at least weekly, or whenever the water looks cloudy or the tube has deposits. Algae and bacteria can grow in water left standing for long periods, especially in warm, bright rooms.

Last Updated: September 2026