You should indicate the name of the test tube next time though

@ProfessorDrewCollop

2 жыл бұрын

Thanks for the feedback. The purpose of this video for viewers to determine what each of the test tubes contain. If I wrote the name on the test tube, it would defeat the whole purpose of the video. I just recorded new version of this video and plan to release it in the coming weeks. The new one will have audio. This one does not, as I did not know how to do that when I started creating. I have learned a lot in the past year.

what is the name of #5 to #12?

@ProfessorDrewCollop

3 жыл бұрын

I cannot tell you which is which as this video is for a lab simulation. The goal of the video is for the students to determine the identity of each. I will provide a list (sorted alphabetically) of the possibilities in the description.

Is there maltose there or no?

@ProfessorDrewCollop

3 жыл бұрын

Maltose is a Disaccharide so it was eliminated in the previous reaction (Barfoed's Test). Only Monosaccharides were assessed using Bial's Test.

@qingyuli5460

3 жыл бұрын

@@ProfessorDrewCollop thank youu😅

why pentoses show bluish colour while hexoses do not?

@ProfessorDrewCollop

2 жыл бұрын

Thanks for the question Nour. Bial's reagent contains orcinol (3,5-dihydroxytoluene), hydrochloric acid and ferric chloride. The acid & heat breaks the pentose ring to create furfural. The furfural will then react with orcinol and the iron ion to form a blue precipitate. Hexose rings will also be broken by the acid & heat but creates hydroxymethyl-furfural. This also reacts, but because the chemistry is different it does not create a blue precipitate. Hope this helps.

@nourkauteich141

2 жыл бұрын

@@ProfessorDrewCollop thank you Professor ❤!