To collect quantitative data, scientists use all of the following except

1.a stopwatch

2.rulers

3.descriptive categories

4.scales
(this is science)

You would use all of the following except for 3. descriptive categories because, that is a qualitative observation using descriptions and not a quantitative observation using numbers.

The answers would be: 1: the liquid only contains one compound4: the liquid is a pure substance

Iwas going to ask that quesytion  sorry dude i dont  know : (    : /