Aim
Aim: To neutralize sodium hydroxide using hydrochloric acid. Method: A one cm strip of litmus paper was placed into a test tube and then sodium was added into the test tube to depth of 1 cm. Hydrochloric acid was added into the test tube drop by drop until the first permanent colour of the litmus paper appeared. The test tube was then swirled again to ensure of the colour change. 1 drop of sodium hydroxide was added into the test tube. It was observed to see if the litmus paper changed. More sodium hydroxide was added until the point of neutralisation, meaning when one drop of acid or base can cause the litmus paper to change immediately. The litmus paper was taken out and a small amount of the solution was poured into an evaporating dish.