Suppose you had to test how well two types of soap work. describe your experiment by using the terms control, variable, reproducible, and repetition.

Soap controls its cleansing action with the help of sodium or potassium ion linked to terminal of fatty acid chain which lower down the surface tension of water and causes cleansing action

Hydrophobic end linked with greese or stain and pull it out wiht the help of hydrophillic terminal which is linked to water.

Soap is long chain of fatty acid forming ester linkage with glycerol. These long fatty acid chain may varies or they may be variable according to the action of soap such as detergent mostly having  long chain fatty acid.

The hydrophobic chain remain out of the water molecule whereas hydrophillic remain towards the water molecule and this process produce miscelles. After that this process repeated for other two fatty acid chain .

For creating further froth little amount of soap or detergent is required as the sodium or potassium ion still present in water and its easy for little concentration of soap to reproduce micelles again.

The repeated carbon in long fatty acid chain get dissolves in greese or oil particle and thus helps in removing the stain.