Halogens React with Sodium Hydroxide

Chlorine + Sodium Hydroxide

Cl2 + 2NaOH → NaCl + NaOCl + H2O

Observation:

The greenish chlorine gas dissolves quickly in sodium hydroxide, forming a colourless solution.

Discussion:

Chlorine gas react with sodium hydroxide to form salt of sodium chloride, sodium chlorate(I) and water.

Bromine + Sodium Hydroxide

Br2 + 2NaOH → NaBr + NaOBr + H2O

Observation:

The reddish-brown liquid bromine dissolves in sodium hydroxide, forming a colourless solution.

Discussion:

  1. Bromine liquid react with sodium hydroxide to form salt of sodium bromide, sodium bromate(I) and water.
  2. The reaction is less reactive compare with chlorine.

Iodine + Sodium Hydroxide

I2 + 2NaOH → NaI + NaOI + H2O

Observation:

The black iodine crystals dissolve slowly in sodium hydroxide, forming a colourless solution.

Discussion:

  1. The reddish-brown liquid bromine dissolves in sodium hydroxide, forming a colourless solution.
  2. Solid iodine react slowly with sodium hydroxide to form salt of sodium iodide, sodium iodate(I) and water.
  3. The reaction is least reactive among the three.

Safety Precaution

  1. Fluorine, chlorine and bromine gases are poisonous.
  2. Therefore all the experiments involving these gases should be carried out in a fume chamber.
  3. The experiments involve fluorine are nor done in school.
  4. This is because fluorine is so reactive that it will react with most of the substance it comes into contact with.
  5. It is very difficult to conduct experiments involving fluorine.


3 comments:

  1. Don't read this anyone, it makes no sense, the equations are wrong and unbalanced and the chemistry is flawed

    ReplyDelete
    Replies
    1. Yes, Henry was right! We miss out the H2O in the equation and hence the equation is imbalance. Thank you for correcting us. :)

      Delete
  2. Not only missed out the H2O, but your equations are wrong too! e.g your initial Cl is 2, but outcome got 4. Same to other halogen (Br & I).
    Noticed your Malay version is totally wrong too.

    ReplyDelete