Water test strips?

Question

can they be used over again

Answer 1

The general answer is no. The uncertainty in the readings would be very great, even if you got a reaction with a new sample. They are created to be used once. In most cases, the best scheme is to cut them into pieces if they are the color change type and do not have a scale or multiple tests on them (like litmus paper). Otherwise, they are single use.

Answer 2

no