This is related to a biology lab I did. What is the purpose of adding sand to hydrogen peroxide (and put at a glowing splint at the mouth of the tube)?

The purpose of this lab was to study the action of the enzyme catalase (potato)on hydrogen peroxide and to determine the conditions that affect this activity.

Thanks in advance.

Sand + H2O2 is a non-reactive mixture. The catalase test will froth in peroxide if present. The sand may have been a test of total inertness.

The purpose of adding sand to hydrogen peroxide in the biology lab you did is to test for any non-specific reactions or observed frothing that may occur. By adding sand, which is inert and non-reactive, you can determine if any frothing or reaction you observe is due to the presence of the enzyme catalase or if it is simply a non-specific reaction.

In this lab, the objective was to study the action of the enzyme catalase found in potatoes on hydrogen peroxide and investigate the factors that influence its activity. Catalase is an enzyme that breaks down hydrogen peroxide into water and oxygen gas. When hydrogen peroxide comes into contact with catalase, it rapidly decomposes into water and oxygen, creating a frothing or bubbling effect.

To confirm that the observed frothing is specifically due to the catalase enzyme and not any other factors, it is important to have a control group. By adding sand, which is inert and won't react with hydrogen peroxide, you can compare the reaction (or lack thereof) in the sand and hydrogen peroxide mixture with the reaction seen in the presence of the potato extract (containing catalase).

By placing a glowing splint at the mouth of the tube containing the sand and hydrogen peroxide mixture, you can notice if there is any oxygen gas being produced. If the sand and hydrogen peroxide mixture shows no frothing or gas production, but the potato extract does show frothing and gas production, then it indicates that the observed reaction is specific to the presence of catalase in the potato extract.

Overall, adding sand and using a glowing splint helps to distinguish between non-specific reactions and the enzymatic activity of catalase in the potato extract.