carboxylic acids (1 Viewer)

[AnAn]

1)how many barboxylic acid exist, which satisfy the overall formula C5 H10 O2 ? name all such compounds

2) ken was baking muffins for his lunch at school. he misread the label on the recipe and added too much baking soda. when he removed his blueberry muffins from the oven, his muffins had turned Green but not blue. what happeded to Ken 's muffins?

 

[CM_Tutor]

I can think of 4 different carboxylic acids C₅H₁₀O₂, which are:

pentanoic acid
2-methylbutanoic acid
3-methylbutanoic acid
2,2-dimethylpropanoic acid

This ignores geometric isomers, which aren't covered by the HSC syllabus.

As for the second question, what do you know about the acid / base properties of baking soda?

 

[xiao1985]

cm_tutor, i am unsure abt this q... bakin soda is basic right??? so blue berry is a natural indicator???

 

[~*HSC 4 life*~]

Just say that the addition of too much baking soda caused the muffin mix to become basic. The higher ph of this mixture caused the muffins to turn green and not blue

 

[CM_Tutor]

I skipped the second question because I had some doubts about it. Baking soda itself is certainly weakly basic, and I was guessing the question wanted a discussion of indicators, but the fact that baking soda undergoes a decomposition reaction when heated, coupled with the fact that carbon dioxide - an acidic oxide - is produced, had me wary of the question. The 'correct' answer depends a bit on how much chemistry the marker knows...

 

[spice girl]

Originally posted by CM_Tutor
I skipped the second question because I had some doubts about it. Baking soda itself is certainly weakly basic, and I was guessing the question wanted a discussion of indicators, but the fact that baking soda undergoes a decomposition reaction when heated, coupled with the fact that carbon dioxide - an acidic oxide - is produced, had me wary of the question. The 'correct' answer depends a bit on how much chemistry the marker knows...

but won't the Na+ ions left behind make the muffin basic? the only anions that could possibly be left behind is the hydroxide ion.

 

[xiao1985]

y does alkalinity promot blue color???