Question

Experiment 1: Neutralization of Acids and Bases In this experiment, you will leam how to properly neutralize and dispose of acidic and base solutions Remember, when a solution has a pH of 7, it is considered neutralized Materials 5 mL 4.5% Acetic Acid (vinegar), CHaO (1) 250 mL Beaker (1) 10 mL Graduated Cylinder 1)100 mL Graduated Cylinder (8) Litmus Test Strips 0.5 g Sodiunm Bicarbonate (baking soda), NaHCO (2) Weigh Boats "Water Permanent Marker Neutral) (2) Pipettes You Must Provide Procedure 1. Use the permanent marker to label two of the weigh boats as A and C 2. Use the permanent marker to label a 250 ml beaker B 3. Set the containers in the order A B, and C 3 4 5 6 7 8 9

Answer 1

Initial litmus test result

A it contains pure water so the neutral litmus strip of orange colour changes to very light green colour Nd pH will be 7

B it contains the mixture of 0.5g sodium bicarbonate and 100ml water so solution being the basic in nature will have higher pH above7 and lies between 7.5 to 8 the colour of litmus changes to green.

C it contains vinegar which is a acid a weak acid so it's pH will be less than 7 and lies between 2to 3 the colour litmus will change to dark orange.

Table 3 neutralisation

1ml of vinegar into solution b will not cause colour change it will remain green

2ml of vinegar into solutionb will not cause remarkable colour change and litmus remain green in colour

3ml of vinegar to the solution b will start the neutralisation reaction and the colour change would start toward light green

4ml of vinegar to the solution b will cause the colour of the litmus to be pale green

5ml of vineger to solution b will cause the colour of litmus to be very light green colour and the Ph of the solution would be 7.

Post lab questions

2) neutralisation reaction - The reaction between the acid and base which leads to the formation of salt and water is termed as neutralisation reaction.

3) Neutralisation reaction has number of uses in laboratory setting like in acid base titration using phenolphthalein as indicators, in calculating the normality or molarity of solution .

Some strong acids after its use are also neutralised before draining them out.

4)The solution of beaker B was neutralised at pH 7 because this is the neutral point .and both acid and base are cimpcomple neutralised at this pH.

5) strong solution of sodium bicarbonate would have initial pH around 8.1 and for its neutralisation large amount of vineger would have been needed because than only large amount of hydrogen ion could come and neutralise hydroxyl ions.But in weak sodium bicarbonate solution the vineger is used less due to weak concentration of hydroxyl ion.