Question

A biologist wants to test some lake water for the presence of nitrates.he has a sensor that detects even the tiniest amount of nitrates by turning an internal light from green to red.

1. What will be his positive control?
2.what will be his negative control ?
3.why does he need to include these control?

Answer 1

a) the positive is that he will obtain pure water and nitrogen. b) the negative is that he will obtain carbon(iv)oxide.c) the reason for the applicant of this controls is that nitrogen he will obtain will be used for laboratory preparations.

not sure if this is completely correct hope this helps