Congo red
Congo red · Congo reds
An azo dye that turns red in alkaline, blue in acidic solutionsAn azo dye that turns red in alkaline, blue in acidic solutions.
Meaning
1 senses(countable, uncountable)An azo dye that turns red in alkaline, blue in acidic solutions.
a red-brown azo dye especially as a chemical pH indicator (congo red is red in basic and blue in acidic solutions)
Forms
plural: Congo reds| Singular | Congo red |
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| Plural | Congo reds |
regular
Lessons for this word
1 lessons- A1Countable and uncountable nouns — Because it can be uncountable