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Application of Gay-Lussac’s Law of Combining Volumes

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

WAEC 2023 Exams Preparatory Class on the Analysis of Lead Trioxonitrate V

      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

Stoichiometry Tutorial Step by Step

  Stoichiometry is the study of the quantity of the reactants and products involved in a chemical reaction. It can also be defined as the determination of the ratio in which elements or compounds react with one another in a chemical reaction. Method Calculating Stoichiometric Problems In stoichiometric calculation, the basic method of calculating the problems is by converting one quantity to another using the conversion factors which are usually found in a balanced chemical equation. These conversion factors are the important ratios which can be turned into a fraction to produce the desired results. The molar mass of a substance is one of the important conversion units which is defined as the mass of one mole of a substance expressed in grams. Types of Stoichiometry Calculations or Problems There are four basic types of stoichiometry calculations which include: 1.        Mass-to-mass conversion 2.        Mass-to-mole conversion 3.        Mole-to-mass conversion 4.    

Faraday's Laws of electrolysis

  Faraday’s Laws of Electrolysis Faraday put forward two laws of electrolysis and he also discovered from his experiment that the quantity of products of electrolysis depends on the following Time of the flow of electric current The ionic charge of the element deposited The amount of current Faraday’s First Law of Electrolysis The first law states that the amount of the element deposited during electrolysis is directly proportional to the quantity of electricity passed through the electrolyte (electrolytic solution). Mathematically       M ∞ Q Where  Q = quantity of electricity measured in Coulomb M = mass of the substance deposited Since the quantity of electricity is given by Q = current x time in seconds Faraday’s first law can also be stated as “the mass of element deposited during an electrolysis is proportional to the size of the current and the time taken for the flow of the current.”    M ∞ I x t  Or  M = є I t Where є is a constant called electrochemical equivalent. I sta