Acids, Bases, and Buffers Lab

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Acids, Bases and Buffers Lab

Acids, Bases and Buffers Lab
The experimental results for part one is as follows:
Part One Data Table
| Initial pH| Final pH|
Test Tube A| 6| 1|
Test Tube B| 4| 4|
Test Tube C| 4| -----|
Test Tube D| 4| 4|
Test Tube E| 6| 11|

The experimental results for part two is as follows:
Part Two Data Table
| Before CO2 was Added| After CO2 was Added|
Colour| Blue/green| Light green/yellow|
pH Level| 8.0pH| 5.0pH|

For thousands of years, people have known lemon juice, vinegar, and many other foods taste sour. However, it was not until a few hundred years ago that it was discovered that these foods tasted this way because they were all acids. In the seventeenth century, the Irish writer and amateur chemist Robert Boyle first labeled substances as either acids or bases. He noted that acids tasted sour, are corrosive to metals, change litmus red, and become less acidic when mixed with bases. On the contrary, bases felt slippery, changed litmus blue, and became less basic when mixed with acids. In the late 1800s, the Swedish scientist Svante Arrhenius believed that acids are compounds that contain hydrogen and can dissolve in water to release hydrogen and can dissolve in water to release hydrogen ions into solution. He also defined bases as substances that dissolve in water to release hydroxide ions into solution. Finally, in 1923, the Danish scientist Johannes Bronsted and the Englishman Thomas Lowry altered Arrhenuis’ theory slightly, saying acids and bases are substances that are capable of splitting off or taking up hydrogen ions respectively. In 1909, the Danish biochemist Sören Sörensen invented the pH scale for measuring acidity. The pH scale ranges from 0 to 14, where substances with a pH between 0 and less than 7 are acids, substances with a pH greater than 7 and up to 14 are bases, and a substance is considered neutral when they have a pH level of 7.

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