Gay Lussac’s of combining volumes states that gases react in simple ratio with one another and to volumes of the products provided that temperature and pressure remain constant. In this article, you will understand how to apply this law in calculation by studying the following examples below: 1. 2H 2 + O 2 → H 2 O In the reaction above, what volume of hydrogen would be left over when 300cm 3 of oxygen and hydrogen are exploded in a sealed tube? 1cm 3 of oxygen = 2cm 3 of hydrogen 300cm 3 of oxygen = 2 x 300 = 600cm 3 Volume of left over = 1000 – 600 = 400cm 3 2. Calculate the volume of carbon (II) oxide required to react with 40cm 3 of oxygen. 2CO + O 2 → 2CO 2 1cm 3 of oxygen = 2cm 3 of CO 40cm 3 of oxygen = 2 x 40 = 80cm 3 3. Calculate the volume of residual gases that would be produced when 100cm 3 of sulphur (IV) oxide reacts with 20cm 3 of oxygen 2SO 2 + O 2 → 2SO 3 1cm 3 of O 2 = 2cm 3 20cm 3 of O 2 = 2 x 20 = 40cm 3
The analysis of lead trioxonitrate V can be done using different tests to help identify the ions present in the compound. This tutorial class will be based on one of the several methods of testing for the ions in lead trioxonitrate V salt. Procedure: Put some lead trioxonitrate V salt sample into a test tube and add about 10 cm 3 of distilled water, then shake very well to dissolve. Divide the solution into five portions. 1. To the first portion, add dilute sodium hydroxide solution in drops then excess. A white precipitate which is soluble in excess dilute sodium hydroxide indicates that zinc ions, aluminium ions or lead ions might be present in the solution. 2. Add aqueous ammonia in drops then in excess to the second portion. A white precipitate is formed which is insoluble in excess aqueous ammonia indicating that zinc ions are absent and aluminium ions or lead ions might be present. 3. To the third portion, add dilute hydrochloric