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...
Matter has different types of particles, such as atoms, ions, molecules, etc. An element is made up of atoms. A mole is used to represent the number of atoms in an element just as a crate is used to represent 30 eggs. Avogadro’s number is the number of units in a mole of any substance and it is equal to 6.02 x 10 23 . Therefore, one mole of any substance is represented by 6.02x10 23 . A diatomic element like chlorine is 6.02x10 23 molecules of chlorine. One mole of tetraoxosulphate (VI) oxide and one mole of methane each represents 6.02x10 23 molecules of these compounds. Similarly, sodium and calcium elements each also contain 6.02x10 23 atoms. Example Question 1 How many atoms are there in 10g of sodium? (Na = 23, Avogadro’s number = 6.02x10 23 ) Since one mole is equal to 6.02x10 23 and one mole is equal to relative atomic mass expressed in grams. 1mole = 6.02x10 23 1mole = 23g 23g = 6.0...