pH Lab

Click on a test strip to dip into each solution. Then, compare the color change to the pH scale on the left and record the value in the numbered boxes above. Keep a paper record of the values post later in the lab discussion.

Click “Submit” to check your answers. Reset and repeat experiment sets until you get pH results for 12 different solutions.

To indicate the acidity or basicity of a solution we use a pH scale that runs from 0 to 14. The scale measures the number H+ and OH- ions in a solution. Acids have more H+ ions. The lower the pH value, the stronger the acid. Bases have more OH- ions. The higher the pH value, the stronger the base. We typically refer to pH 7 as neutral since its H+ and OH- ions are balanced. Most liquids fall somewhere above or below pH 7. Many foods have acids added to them (example vinegar) to inhibit microbial spoilage. Also, changes in normal pH in specific body fluids (such as blood or urine) can be linked to specific illnesses.

In this exercise, we will use pH strips to determine the pH of different solutions. Be sure to record your answers before you reset each test set so that you have a record of your results. Run the experiment 3 – 4 times or until you test at least 12 different solutions.”