Non essential clause

[pappup5]

Hi Ron,

I am modifying one of my older questions to make it as close as possible to the one from OG . This is a question that I just made up.

Chemicals X and Y are formed from the evaporation of sulfuric acid that is
heated in a flask and rises high up the capillary tube, condensing in tiny
droplets on minute particles of slag.

Warmed in a flask, sulfuric acid evaporates, rises high into the
capillary tube, and condenses in tiny droplets on minute particles of slag
to form chemicals X and Y.

If I were to correlate, the above would be equivalent to the correct answer. My question is that when the subject is used in a non essential clause is the clause "non essential "? I mean if I ignore the sentence bounded by commas on both ends ,the sentence will not make sense. So, just wondering whether there is a special rule governing non essential clause.

[RonPurewal]

i don’t know the terminology, so i can’t speak to that part of your question… but it is absolutely impossible to remove anything other than ‘Warmed in a flask’.

the main sentence comprises all of the remaining parts: it’s saying that sulfuric acid does thing #1, does thing #2, and does thing #3.
these things are not modifiers. rather, this is just a list of three things (‘A, B, and C’), punctuated in the usual way.

[RonPurewal]

also, this thread is a perfect example of why terminology is actually counterproductive, excepting only the most basic elements (noun, verb, etc.)

if you just look at this sentence and think about what it is saying, it should be perfectly clear that you're looking at a list of three sequential actions, none of which can be 'removed'.
...but, by trying to put names/labels on everything, you've just pushed that common sense out of your brain. not good.

[pappup5]

Thanks Ron, Actually I am not one to terminology blindly - apologies if the question presents that image. Actually,long GMAT questions involving
multiple commas take a little while to breakdown so I was basically looking for a quick way to eliminate at least a few choices.

I have a car, a pen and a house - This is a more conventional list form. But the sentence above sounded more like a sequence of events
and I was a little unsure of how the subject was placed.

[RonPurewal]

long GMAT questions involving multiple commas take a little while to breakdown

ok, see, THIS ^^ is the problem.

these words imply that you're trying to 'break down' the sentence BEFORE you think about its meaning.

perhaps you don't mean that. (if you don't, then, great!, but be sure to understand the gravity of this point anyway.)
if you DO mean that, though, then you're making a grievous error.
you should ALWAYS understand EXACTLY what the sentence should say BEFORE you investigate grammar.

because...

...1/
well, it's NECESSARY.
it's IMPOSSIBLE to determine whether grammatical structures are 'correct' or 'appropriate' without a pre-existing understanding of the intended meaning.

and...
...2/
WITHOUT a sense of intended meaning, most sentences (especially longer ones) can be 'broken down' in multiple ways. WITH an intended meaning, there's just ONE way.
(this is why human languages NEVER EVER EVER look like programming languages. in a programming language, every construction has to do exactly one thing, all the time, every time. if a human language were to work like that, it would be at best exasperating, and at worst completely unworkable in real time.)

step 1 is step 1.

[RonPurewal]

and I was a little unsure of how the subject was placed.

see, this sort of difficulty ^^ will abate, more or less completely, once you start taking the time** to understand the intended meaning FIRST.

from your initial reading, it should be %100.00000 crystal clear that 'This is a sentence about what sulfuric acid does.'
this understanding is neither complex nor subtle—but it's all you need to understand the structure VERY quickly.

[RonPurewal]

one last thing—

I have a car, a pen and a house - This is a more conventional list form.

this will almost certainly never become an issue, but this is not how lists are punctuated in the variant of standard american english used on the gmat.

on the gmat**, lists of 3 or more things will ALWAYS be punctuated like this:
X, Y, and Z

...and NEVER like this:
X, Y and Z

--

**the same convention is followed in most US sources—excepting mostly those in which space is at a huge premium, such as newspapers.

[RonPurewal]

note what i said above:

this will almost certainly never become an issue

'okay, ron, then why are you wasting my time?'

good question.
the point is that if you see the version that's NOT a list—namely, 'X, Y and Z'—then you're looking at a different kind of construction, with a different meaning. in most (BUT NOT ALL) cases, this means that 'Y and Z' is a modifier of 'X'.

e.g.,
Stefan attended the talk with Roy, his longtime friend and his company's chief investor.

versus
Stefan attended the talk with Roy, his longtime friend, and his company's chief investor.

both of these are legitimate sentences, but they have very different things to say about who attended the talk.

what do they mean?
(scroll down AFTER you try to spell it out)

[RonPurewal]

Stefan attended the talk with Roy, his longtime friend and his company's chief investor.

here, stefan attended with ONE other person.
this person's name is roy.
roy is stefan's longtime friend.
roy is also the chief investor in stefan's company.

Stefan attended the talk with Roy, his longtime friend, and his company's chief investor.

here, stefan attended with three different people.
presumably the reader already knows who roy is; otherwise this sentence would just be weird.
also, this sentence implies that stefan has only one 'longtime friend' (who is neither roy nor the investor).

[pappup5]

Thanks a lot Ron for such an informative response. I really appreciate the number of takeaways that you have provided.
My problem was lack of clear judgment when deciding between modifier and list, but I have a clear understanding of the two now.

Cheers!!

[RonPurewal]

ok.