Making Salts

Aim: The aim of the experiment is to produce sodium chloride salt by carrying out a neutralisation reaction.

Hypothesis: By balancing the mixture of acid and base [NaOH + HCl] we are able to reach neutralisation. Using the method of evaporation we should be able to create sodium chloride.

Equipment: The equipment is as follows:

• 50 & 200ml beakers.
• HCl
• NaOH
• 25ml measuring cylinder
• Glass stirring rod
• Spotting tile
• Universal indicator solution
• Hot plate
• Gauze mat
• Dropper

Method: 

1. Using the measuring cylinder measure 10ml of HCl and pour it into your 50ml beaker. 
2. Add dilute NaOH a few drops at a time while stirring with a glass rod. 
3. Every 10-15 drops stop adding the NaOH and use glass stirring rod to transfer a drop of the solution spotting tile. Test its pH using Universal indicator.
4. Keep adding NaOH and testing the solution by repeating step 3. As you get closer to neutral you may need to test the solution after every drop.
5. Pour the neutral solution into an evaporation basin (in our case a different beaker) and evaporate the water from the solution using the equipment shown above.

Observation:  

The colours change from the warm colours[reds] to the colder colours--specifically violet. Though through addition and getting closer to neutralisation the colours such as yellow, orange, lime as starting with an acid. However, if started with the base it would then [as it gets closer to neutralisation] turns indigo, blue, sky blue to green. 

Word Equation:

Acid + Base --------> Salt + H2O   

or

NaOH + HCl -------> NaCl + H2O