Ph Measurer Lab Report

Throughout the experiment, there were 3 significant error I made. Firstly, at first when I conduct my experiment, I measured 10g of ascorbic acid powder and mix it within 1 litre of water. I believed that by having the solution prepared before putting in the d-block elements would save time overall. Unfortunately, the data was all over the place, this is because the later I conduct the experiment, there is a higher chance of oxidation occur in the ascorbic acid solution as it have a direct contact with oxygen in the atmosphere. In order to keep constancy, I had to reduce the amount of ascorbic acid by ratio to 0.2g with 10ml of water. By measuring element for each trial, it is easier to control the rate of oxidation to have a data with higher precision.
The reason why I think this could be a limitation is because each solution has an extreme acidic pH level like 1 or 2. As a result, I speculate the supreme acidity of the solution could negatively affect the pH measurer that could make it lose the originality to measure the right pH level for later product. Hence, it is crucial to have the pH measurer calibrated in a buffer solution so that the measurement can have a high accuracy overall. Thirdly, when measuring the enthalpy change for the solution, it is suggested to measure the temperature of the ascorbic acid solution for 30 seconds before putting in the d-block element in order to have a plateau temperature of the original solution in order to compare with the product temperature later. In my experiment, I waited 30 seconds for the ascorbic acid power to dissolve in water, I should have measured the temperature then put in the element to have more data to support the enthalpy change