Aim:
We want to find out which of the substances are acidic, base, or neutral.
Equipment:
- Spotting tile
- Litmus Paper
- Substances to test.
- Universal Indicator
- Pipettes
Method:
- Gather all your equipment.
- Add a drop of universal indicator into the spotting tile.
- Add the liquid or substance of your choosing to the spotting tile with the universal indicator and watch it change color.
- Add the litmus paper and see what color it changes into.
- If you have another piece of litmus paper dip it into the liquid again.
Results:
https://docs.google.com/document/d/1HvlCXIvJDdk-6Z5iysJ0jEz6KSHxwoPqShyk-3ahONg/edit?usp=sharing
Discussion:
As we did the experiment, each liquid had a different color as we added the universal indicator. The reason why this happens is because of its pH level, pH levels determine if the liquid is acidic, neutral, or base. If the liquid was acidic it would have a high hydrogen (H+) level as acids have a lot of hydrogen ions. If it were a base it would have a lot of hydroxide ions (OH-) to it as it is a base. If it was netural both of these ions would be balanced.
How we know if the liquid or chemical is acidic or a base is because it will change color to red or blue. If the liquid was acidic it would turn red as we added the universal indicator and if it was a base it would turn blue. Another way of telling if it is acidic or a base is by litmus paper. Now there is a red litmus paper and a blue litmus paper. If you dip a red one in and it stays that same color it means that it is acidic, but if it turns blue it means that it is a base. The same thing with the blue litmus paper, if it stays the same color it is a base but if it changes color to red it is an acid.
If you ever do this experiment, the universal indicator would be a better choice than the litmus paper. The reason why this is is because the universal indicator can change to a variety of colors and is helpful in specifying the strength of the acid or alkali.
Conclusion:
- Did all your experiments work – if they didn’t, why? – Yes all of our experiments did work. The reason why are experiments were successful is because we followed the steps we were meant to do.
- What could you do to improve your science next time? Think about the reliability of your data – What we could have done differently is that we should have cleaned the pipettes for each liquid we used it on. The reason for this is that if we don’t clean it, and use it again the two substances would mix. For example, if I used toilet cleaner first and then floor cleaner, the two would mix and it would have some of the toilet cleaner in the floor cleaner.