This means that a chemical is added, drop by drop, to a sample until a certain color change (blue to clear, for example) occurs.
(a certain color change; occurs; ) (This; means; that a chemical is added, drop by drop, to a sample until a certain color change (blue to clear, for example) occurs) Context(This means,List([0, 10))):(a chemical; is added; to a sample)
This means,List([0, 10))
a certain color change This a chemical
occurs means is added
that a chemical is added, drop by drop, to a sample until a certain color change (blue to clear, for example) occurs
to a sample