Atoms, the smallest unit of matter, are made up of an equal number of

Question

Project SC Butler: Day 127 Sentence Correction (SC1) 
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Atoms, the smallest unit of matter, are made up of an equal number of protons and electrons, but if a single electron is lost or gained,  it becomes an ion, a charged particle that can combine with other ions to form an electrovalent bond.

A)Atoms, the smallest unit of matter, are made up of an equal number of protons and electrons, but if a single electron is lost or gained,

B) An atom, the smallest unit of matter, is made up of an equal number of protons and electrons, but if the atom loses or gains a single electron,

C) Atoms, the smallest unit of matter, are made up of an equal number of protons and electrons, but if a single electron is lost or gained from them,

D) The smallest unit of matter, atoms are made up of an equal number of protons and electrons, and when a single electron is lost or gained,

E) Made up of an equal number of protons and electrons, an atom, the smallest unit of matter, until a single electron is lost or gained,

The official explanation will be posted on Friday, June 22, 2019.

generis · Answer

OFFICIAL EXPLANATION

Project SC Butler: Day 127 Sentence Correction (SC1)

Atoms, the smallest unit of matter, are made up of an equal number of protons and electrons, but if a single electron is lost or gained, it becomes an ion, a charged particle that can combine with other ions to form an electrovalent bond.

A) Atoms, the smallest unit of matter, are made up of an equal number of protons and electrons, but if a single electron is lost or gained,

B) An atom, the smallest unit of matter, is made up of an equal number of protons and electrons, but if the atom loses or gains a single electron,

C) Atoms, the smallest unit of matter, are made up of an equal number of protons and electrons, but if a single electron is lost or gained from them

D) The smallest unit of matter, atoms are made up of an equal number of protons and electrons, and when a single electron is lost or gained,

E) Made up of an equal number of protons and electrons, an atom, the smallest unit of matter, until a single electron is lost or gained,

****
The sentence means that an atom
-- is the smallest unit of matter and
-- has an equal number of protons and electrons
BUT when the atom either loses or gains a single electron
-- the atom becomes an ion
The sentence ends with a dispensable appositive that describes an ion: a charged particle that can combine with other ions to form an electrovalent bond

***
• Split #1: Pronoun/antecedent agreement

It in the non-underlined portion lets us know that the subject is singular.
IT requires the singular ATOM as its antecedent.

I did not mark the plural verb ARE with red because are agrees with atoms and I did not want to suggest that atoms disagreed with are.

Options A, C, and D incorrectly use atoms, plural.

Eliminate A, C, and D

• Additional problems with A, C, and D

The electron does not become an ion. The atom becomes an ion.
Options A and D create a very subtle meaning issue because IT almost certainly refers to electron, in which case the electron becomes the ion.

Could "it" refer to "unit"? -- -- Maybe: Now we have pronoun ambiguity. Does "it" refer to electron or to unit?
-- Probably not: to be perfectly parallel, the appositive modifer unit of matter should say units of matter. I left this issue alone because the easiest way to eliminate A, C, and D is the disagreement between the non-underlined IT and plural atoms.

I would not use this issue as a first basis upon which to eliminate an answer in these choices that use plural "atoms."

Suppose, though, that option A were written this way:

An atom, the smallest unit of matter, is made up of an equal number of protons and electrons, but if a single electron is lost or gained, it becomes an ion, a charged particle that can combine with other ions to form an electrovalent bond.

Compare to option B.
No contest. B wins. In my hypothetical option A, it seems as though the electron becomes the ion. At the least, we do not know whether the thing that becomes an ion is the electron or the atom.
The electron does not become the ion. The atom becomes the ion.

Option C - from them
The phrase is awkward, but the phrase does intervene to head off the meaning problem I just discussed.
Even if the sentence were okay otherwise, B does a better job at letting us know which thing becomes an ion.

• Split #2: Clarity vs. The Missing Verb or Unnecessary Pronoun or Babble

We are down to options B and E.
Sometimes options are laughably bad, as is E in this question.

warrior1991 's comment about option E made me laugh: "This sounds creepy."

Believe me, you will find a sentence or two in which that thought ought to enter your mind.

Quote:

If you read the complete sentence, the construct is awkward. This sounds creepy.A run on as well. Read below.
Made up of an equal number of protons and electrons, an atom, the smallest unit of matter, until a single electron is lost or gained, it becomes an ion, a charged particle that can combine with other ions to form an electrovalent bond.

I quote the entire comment because he's right: describing an error may not be easy, but we can both insert the option into the sentence and compare that construction to (B); even if we cannot quite say what is wrong with (E), we can say, "B is better and E is worse. Bye E. The end."

Option E contains one of these errors
1) if we say that the first part of the sentence ends with "gained," then atom lacks a verb.
2) we could also say that IT comes between the subject, atom, and the verb, becomes, in which case we have an unnecessary pronoun
3) the sentence structure in (E) is not nearly as clear as that in (B)

Answer B

COMMENTS

firas92 , you also made me laugh, grousing (or wondering) about what were indeed typos that I've corrected.

Although this question is unusually easy, every post contains some piece of advice or an approach or a comment that will apply to similar but harder questions.

These answers are very good to superb. Good work. Kudos to all.

Believe me, you will find a sentence or two in which that thought ought to enter your mind. I quote the entire comment because he's right: describing an error may not be easy, but we can both insert the option into the sentence and compare that construction to (B); even if we cannot quite say what is wrong with (E), we can say, "B is better and E is worse. Bye E. The end." Option E contains one of these errors 1) if we say that the first part of the sentence ends with "gained," then atom lacks a verb. 2) we could also say that IT comes between the subject, atom , and the verb, becomes , in which case we have an unnecessary pronoun 3) the sentence structure in (E) is not nearly as clear as that in (B) Answer B COMMENTS firas92 , you also made me laugh, grousing (or wondering) about what were indeed typos that I've corrected. Although this question is unusually easy, every post contains some piece of advice or an approach or a comment that will apply to similar but harder questions. These answers are very good to superb. Good work. Kudos to all.

Lampard42 · Answer

Meaning: Atoms are made up of an equal number of protons and electrons. When the atom single looses or gains a single electron - the atom becomes an ion which can combine with other ions to form an electrovalent bond.

A)Atoms, the smallest unit of matter, are made up of an equal number of protons and electrons, but if a single electron is lost or gained,   It in the non-underlined portion refers to electron as atoms-plural.

B) an atom, the smallest unit of matter, is made up of an equal number of protons and electrons, but if the atom loses or gains a single electron.  Correct, it here logically refers to atom

C) Atoms, the smallest unit of matter, are made up of an equal number of protons and electrons, but if a single electron is lost or gained from them,  Same error as A

D) The smallest unit of matter, atoms are made up of an equal number of protons and electrons, and when a single electron is lost or gained,  Same error as A

E) Made up of an equal number of protons and electrons, an atom, the smallest unit of matter, until a single electron is lost or gained,  Fragment no verb for atom

firas92 · Answer

Atoms, the smallest unit of matter, are made up of an equal number of protons and electrons, but if a single electron is lost or gained,  it becomes an ion, a charged particle that can combine with other ions to form an electrovalent bond.

The presence of 'it' right after the underlined portion and the usage of "the smallest unit" suggests that the subject must be singular. Therefore, we can eliminate all options that use 'Atoms'

A)Atoms, the smallest unit of matter, are made up of an equal number of protons and electrons, but if a single electron is lost or gained,
Subject is plural - Eliminate

B) an atom, the smallest unit of matter, is made up of an equal number of protons and electrons, but if the atom loses or gains a single electron. 
Seems right - considering that the caps error and full stop are typos!

C) Atoms, the smallest unit of matter, are made up of an equal number of protons and electrons, but if a single electron is lost or gained from them,
Subject is plural - Eliminate

D) The smallest unit of matter, atoms are made up of an equal number of protons and electrons, and when a single electron is lost or gained,
Subject is plural - Eliminate

E) Made up of an equal number of protons and electrons, an atom, the smallest unit of matter, until a single electron is lost or gained,
Awkward wording and distorted meaning - Eliminate

Answer is  (B)

XyLan · Answer

Sentence structure  
 Subject  -  Verb  -  Contrast :
  An atom , the smallest unit of matter,  is  made up of an equal number of protons and electrons , but  
  if  the atom   loses  or  gains  a single electron,  
 it(  the atom  )   becomes  an ion, 
 a charged particle  that(  a charged particle  )   can combine  with other ions to form an electrovalent bond.   - Noun + Noun modifier

Issues:  
 The non-underlined portion asserts "  It  " -  a singular entity  that refers to Atom. 
Thus, all plural forms of atoms MUST be discarded.
 A, C and D  -   Pronoun disagreement

Answer choice analysis:

A)    Atoms , the smallest unit of matter, are made up of an equal number of protons and electrons, but if a single electron is lost or gained,
 -   Pronoun disagreement

B)    an atom , the smallest unit of matter, is made up of an equal number of protons and electrons, but if  the atom  loses or gains a single electron. 
   - Nice and easy.  B  is the champ!   
  C)    Atoms , the smallest unit of matter, are made up of an equal number of protons and electrons, but if a single electron is lost or gained from them,
 -   Pronoun disagreement

D)   The smallest unit of matter,  atoms  are made up of an equal number of protons and electrons, and when a single electron is lost or gained,
 -   Pronoun disagreement

E)   Made up of an equal number of protons and electrons, an atom, the smallest unit of matter, until a single electron is lost or gained,
 Though  E   corrects   the Pronoun-disagreement issue , the sentence structure is inherently   flawed  . 
 E   lacks  a verb for the subject(  an atom) .

TakeAway:  
 Always READ the   entire   sentence.

warrior1991 · Answer

Never ignore the non-underlined part. Many answers can be drawn after reading the non-underlined part thoroughly. The same goes for this question as well

It becomes an ion  ---The it is referring to the atom . But atom is presented in plural form. Therefore we know the S-V agreement is an issue here.

Let's go over the options.

S-V agreement violated. Therefore incorrect.

Good . S-V agreement reached and also the   it    is replaced with   atom  .  Correct

S-V agreement violated. Therefore incorrect.

If you read the complete sentence, the construct is awkward. This sounds creepy.A run on as well. Read below. 
 Made up of an equal number of protons and electrons, an atom, the smallest unit of matter, until a single electron is lost or gained,it becomes an ion, a charged particle that can combine with other ions to form an electrovalent bond.

zhanbo · Answer

My answer is  B . It took me 1 minute and 14 seconds to narrow it down to B via POE.

Issue with A: In reading the original sentence, I did notice that, after the underlined portion, the author uses "it" in ”it becomes an ion“. Since we cannot touch that part, the underlined portion should use singular "atom" as antecedent for "it". A is out. 
Issue with C: Same as A
Issue with D: Same as A / C.
Issue with E: E results in a fragment instead of a sentence.

amitanshumaity · Answer

Atoms, the smallest unit of matter, are made up of an equal number of protons and electrons, but if a single electron is lost or gained, it becomes an ion, a charged particle that can combine with other ions to form an electrovalent bond.

Focus on the construction and the pronoun antecedents.

Atoms--> the smallest unit of matter(Modifier atom)

Atoms are made up of--> Correct SV agreement.

it becomes an ion--> What does it refer to? Atoms? No it can't be as it is singular so it does have a correct antecedent to refer to resulting in illogical meaning.

ion -->a charged particle that can combine with other ions to form an electrovalent bond(Modifies Ion)

Choice B--> An atom, the smallest unit of matter, is made up of an equal number of protons and electrons, but if  the atom  loses or gains a single electron.

but if  the atom  loses or gains a single electron.--> correct contrast and use of the atom corrects the Pronoun agreement error.

IMHO B

baru · Answer

Error analysis : 
 Atoms, the smallest unit of matter, are made up of an equal number of protons and electrons, but if a single electron is lost or gained,   it  becomes an ion, a charged particle that can combine with other ions to form an electrovalent bond.
It here refers to atoms . So we will have to change the underlined sentence as per the antecedent to correct SV pair/pronoun error. .

A) Atoms , the smallest unit of matter,  are made  up of an equal number of protons and electrons, but if a single electron is lost or gained,-wrong

As per the antecedent we need a single atom in the sentence

B)  an atom, the smallest unit of matter, is made up of an equal number of protons and electrons, but if the atom loses or gains a single electron . -Correct
No antecedent error, NO SV error , conveys correct meaning

C)  Atoms , the smallest unit of matter,  are  made up of an equal number of protons and electrons, but if a single electron is lost or gained from them, - wrong 
As per the antecedent we need a single atom in the sentence , in this option atoms is precedent.

D) The smallest unit of matter,  atoms are  made up of an equal number of protons and electrons, and when a single electron is lost or gained,-wrong 
Wrong for the same precedent reason

E) Made up of an equal number of protons and electrons, an atom, the smallest unit of matter, until a single electron is lost or gained, -wrong
Main verb atom is kept in between comma . It results in sentence structure error even though SV pair error is corrected .

Gagan0009 · Answer

" It " in non-underlined portion is pointing toward Atom, So we can remove option containing Atoms.

Atoms, the smallest unit of matter, are made up of an equal number of protons and electrons, but if a single electron is lost or gained,   it  becomes an ion, a charged particle that can combine with other ions to form an electrovalent bond.

A) Atoms , the smallest unit of matter, are made up of an equal number of protons and electrons, but if a single electron is lost or gained, -- Subject verb agreement is not maintained.  It  in non underlined portion require a singular subject. Eliminate.

B)  An atom , the smallest unit of matter, is made up of an equal number of protons and electrons, but if the atom loses or gains a single electron. -- Our Answer

C)  Atoms , the smallest unit of matter, are made up of an equal number of protons and electrons, but if a single electron is lost or  gained from them , -- Again S-V agreement error gained from them again make it like that atom is the one losing a electron. Eliminate.

D) The smallest unit of matter,  atoms  are made up of an equal number of protons and electrons, and when a single electron is lost or gained, -- S-V agreement. Eliminate

E) Made up of an equal number of protons and electrons, an atom, the smallest unit of matter, until a single electron is lost or gained, -- Sentence doesn't contains any verb. Eliminate

generis · Answer

The official explanation has been posted  HERE.

VerbalBot · Answer

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Atoms, the smallest unit of matter, are made up of an equal number of

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Atoms, the smallest unit of matter, are made up of an equal number of

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