1 / 9

Preparation of Oxygen Gas from Bleach

Preparation of Oxygen Gas from Bleach. When bleach is treated with a catalyst the rapid evolution of oxygen gas ensues . Demonstration. NaClO(aq). The commercial bleach was a solution of sodium hypochlorite in water

chad
Download Presentation

Preparation of Oxygen Gas from Bleach

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Preparation of Oxygen Gas from Bleach When bleach is treated with a catalyst the rapid evolution of oxygen gas ensues

  2. Demonstration NaClO(aq) • The commercial bleach was a solution of sodium hypochlorite in water • When treated with a small amount of cobalt(II)chloride the hypochlorite decomposed • 2ClO- (aq) • The bubbles given off were the oxygen gas as concluded from • Pine splint test Catalyst O2(g) + 2Cl-(aq)

  3. Purpose • To use a catalyst to decompose bleach • To collect the decomposition product • To test for the presence of oxygen gas

  4. Concepts 1. Decomposition Reactions 2. Catalysts 3. Collection and Determination of Oxygen

  5. 1. Decomposition Reactions • Decomposition reactions are of the kind A-B • In decomposition reactions, a single substance is converted to more than one new substance • In this demonstration hypochlorite ion decomposes into oxygen gas and chloride ion A + B

  6. 2. Catalysts • A catalyst is a substance which enables a chemical change to occur • A catalyst assists the reactants to convert to products • The catalyst itself may be used over and over: It itself is not changed • When a catalyst is present it is written over the reaction arrow • Addition of a catalyst will speed the rate of many chemical reactions allowing them to occur faster than they otherwise would

  7. 3. Collection and Determination of Oxygen • Oxygen is a gas and is conveniently collected by the displacement of water • A glowing--but not burning--pine splint will burst into flame if oxygen gas is present

  8. Conclusions • Oxygen gas was a decomposition product of bleach • A catalyst was used to cause rapid decomposition • Oxygen was easily collected • Oxygen supported combustion reactions • with a glowing pine splint

  9. Comments • This reaction is not only a decomposition, but also a redox reaction • Bleach should NEVER be mixed with any household chemicals!!!

More Related