• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Electrolysis of Aqueous and Molten Ionic substances

Extracts from this document...


Electrolysis of Aqueous and Molten Ionic substances Electrolysis is 'a chemical change caused by passing an electric current through a compound which is either molten or in solution'. It is essentially the breaking down of a compound by the action of electricity. Electrolysis works only with ionic substances, as they involve charged atoms (ions). Usually, due to the strong electrostatic bonds, ionic substances are hard solids. This means that the electrons are held rigidly in place, they are immobile. So, as electrolysis consists of moving charges (electrons), we require the ionic substance to be aqueous or molten, so the electrons are free and mobile, so can flow to cause a charge. Equipment used during electrolysis: Cathode is negative electrode. Anode is positive electrode. A cation is a positively charged atom and an anion is a negatively charged atom. The anion is attracted to the anode, and the cation is attracted to the cathode. ...read more.


Once you switch on the DC current, you will see bubbling around the anode, and you will find metallic zinc under the cathode after some time. Explanation: Once the power source is connected, the electrodes will be charged and be the anode and cathode.The negative chlorine ion will be attracted to the anode, where it will loose the extra electron to the positive anode, i.e. get reduced. This results in neutral chlorine atoms. These join in a covalent bond with another atom to form chlorine molecules, and are released as a gas. The half equation: 2Cl-(l) --> Cl2(g) + 2e- The positive zinc ions are attracted to the cathode, where they gain the extra electrons (are oxidised), become neutral atoms and sink to the bottom, where they accumulate. The half equation: Zn2+(l) + 2e----> Zn(l) As electrons are used up in the cathode, there are spaces. ...read more.


This again increases global warming. Electrolysis is used in the chlor-alkali industry to gain other useful substances too, such as chlorine, that is used in bleaches and swimming pools, hydrogen, used for making ammonia and margarine and sodium, for making soap, paper, ceramics etc. Hydrogen as fuel in cars Hydrogen is extremely flammable, it has the most amount of energy per gram. It is also a very light gas. If it is directly used in an internal combustion engine, the gas would immediately seep out of the shafts, and when ignited, it will explode violently. So for any kind of use, it needs to be cooled to a liquid. This requires temperatures of -259.14oC, which is extremely hard and expensive to achieve even in a laboratory, and considerably harder to achieve in a medium sized car. Even if all this was possible, the possibility of hydrogen fuel stations are rare, so drivers would need to travel far for one. This is why it is used from water, an abundant material, in fuel cells, using electrolysis. ?? ?? ?? ?? Jagan Annamaraju 10AN ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Physical Chemistry section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related AS and A Level Physical Chemistry essays

  1. Marked by a teacher

    Write an essay on electrode potentials.

    5 star(s)

    Thus, a potential difference is developed between the metal electrode and the adjacent electrolyte. The electrode potential of different metal / metal ion systems are not same as it is closely related to the metal reactivity.

  2. Mole Concept in Gas and Electrolysis

    Calculate the molarity of Na2S2O3 solution. 4.> A vitamin C tablet is dissolved in 150cm3 of 0.5M H2SO4 5.> The mixture is then transferred into a clean 250cm3 volumetric flask and deionized water is added to reach the graduated mark. 6.> Pipette 25cm3 of vitamin C solution (with dil.

  1. Investigating the Rate of the Reaction between Bromide and Bromate Ions in Acid Solution

    I obtained four anomalous results when varying the concentration of bromide ions, which I carried out first, compared with no more than three for any of the other sets of results. This is probably due to becoming more practised at carrying out the experiment over time, so I was less

  2. Describe the construction, operation and application of distillation equipment used in industry

    g entrainment Bubble Cap: Has a high rate of entrainment compared to other trays Sieve Trays: Lower rate than bubble caps, more trays can be fitted in smaller space though giving about even performance over a certain height Valve Trays: Less efficient than sieve trays, lower rate due to less surface area.

  1. Identify an unknown substance through a series of tests that should systematically eliminate all ...

    'Ester can be identified by using phenolphthalein indicator and refluxing with dilute acid or alkali. There should be a colour change from colourless to pink and after warming in water if ester is present the colour should change from pink back to colourless.'

  2. Outline and examine some uses of different metals through history, including contemporary uses, as ...

    electron shell configuration and want to give up or gain electrons to become and become ions. 1. Define the mole as the number of atoms in exactly 12g of carbon-12 (Avogadro ?s number) A mole of any substance is the amount that contains the same number of chemical unit (atoms

  1. Purification of aluminium from Bauxite

    * Then this reaction makes molten calcium silicate in the furnace which can be cold slag * The slag floats on the iron liquid * The iron ore is then heated with carbon to transform it to iron metal Importance of physical and chemical properties of substances Limestone The limestone

  2. Using Catalysts to Manufacture Margarine

    In the manufacture of margarine, nickel catalyst is used as a hydrogenation process to get the right texture on the product (margarine). For example if you want a hard texture, you can raise the melting point of the oil used by hydrogenating it with the nickel catalyst.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work