Use Such and So

[Planetypus]

I think such is a specific word like "I don't have such a thing." Such in this sentence may have an antecedent in a previous sentence.

My question is, when do we use such and so in situations like:

It is unkind of him to ask a little child to do such many things in a day.
It is unkind of him to ask a little child to do so many things in a day.

So in this case, I believe, refers to general things, while such refers to some specific things previously mentioned. Am I right?

I want to learn more.

Many thanks.

[Mister Micawber]

.
It is a syntactic difference, as well as a difference in meaning, PP (but the difference is slight and occasional, and not as you have suggested). Here is how they construct:

Such a thing = that kind of thing (such + a/an + noun)
Such things = those kinds of things (such + noun)
Such stuff (such + noun; the uncountable equivalent of such things)
Such a big thing = of that size (such + a/an + adj + noun)
Such big things (such + adj + noun)

So many things = such a (great) number of things (so + adverb)
So much stuff (so + adv; the uncountable equivalent of so many things)
So beautiful = of that amount of beauty (so + adj; no noun)
So beautiful a day = a day of that amount of beauty (so + adj + a/an + noun)

Of your sentences, only the second is constructed correctly.
.
_________________
Canadian-American native speaker
who teaches English for a living at Mister Micawber's
ESL cafe: Interview with Mr. Micawber

[Planetypus]

Thanks! I find your answers very informative.