How to write Stoichiometric ratio of a reaction?

[wirefree]

Seasons' Greetings.

I have been asked to express the reaction of H2N(CH2)3NH2 with HOOCCH2(C6H4)CH2COOH in a stoichiometric ratio.

Would appreciate some guidance, not with the equation in particular, but the semantics of it.wirefree

 

[sjb-2812]

Can you see what functionality there is in your starting materials that will undergo the reaction?

 

[Borek]

Basically they ask to write reaction equation (that's where the sjb hint comes handy) and to write ratio of the coefficients. For example stoichiometric ratio of KOH to H₂SO₄ is 2:1 (assuming full neutralization is the reaction that is the most obvious one).

 

[wirefree]

I'm half-way there:

For the two compounds, the reaction produces 2 molecules of H2O and NH(CH2)3NHCOCH2(C6H4)CH2CO

Just whose ratio is needed?

Thank you for your guidance,
wirefree

 

[Borek]

Ratio of reacting compounds.

 

[epenguin]

Er, the products of that reaction can themselves undergo the same reaction so there are many products, a mixture of similar things, I don't remember whether this is a common polymer (or rather "copolymer"), obviously the average ratio of the two things in them is 1:1 or close. Seems more a question of pedantic terminology than substance.

 

[wirefree]

I tried 1:1 but it got marked in the red.

What else can I try?

 

[Borek]

Sorry, this is more about a mind reading (what the question author had on mind) than about chemistry.

You have a diamine and a dicarboxylic acid. They can react producing a salt - and they will react 1:1, or 1:2, or 2:1, depending on the ratio of substances mixed. They can react producing amide - again, several ratios are possible, but in the case of long chain being produced (polyamide) stoichiometric ratio is 1:1.

I don't see any better answer than 1:1 and I have no idea what they expect.

 

[wirefree]

Many thanks to all who attempted to address my concerns (& mind-reading the author).

For your reference, the question is part of edX.org's MITx: 3.091x Introduction to Solid State Chemistry course.wirefree