Question

Which of the following compounds has the same percent composition by mass as styrene, C8H8?

A) acetylene, C2H2
B) benzene, C6H6
C) cyclobutadiene, C4H4
D) a-ethyl naphthalene, C12H12

Answer 1

what do you think @mathslover ?

Answer 2

seems what you said earlier wont work

Answer 3

nevermind...the answer is all of teh above...boring question

Answer 4

The ratio of the mass of carbon:hydrogen will always be the same, regardless of the molecule.

If I have 1 carbon atom of weight N and 1 hydrogen atom of weight M, the percent composition will be N/(N+M)% in carbon and M/(N+M)% in hydrogen.

And this relationship scales. Make sense?

Answer 5

I'm trying to think of an analogy to help explain it better.

Answer 6

Ok, I've got one.

Answer 7

Say that the grocery store is selling bags of fruit. Each bag of fruit has 1 apple and 1 orange. Let's assume that all apples have the same mass and all oranges have the same mass.
\[m_A=x; m_O=y\]If I buy one bag, the % composition by mass of apples in the bag will be...\[\frac{x}{x+y} \%\]and the % composition by mass of oranges in the bag will be...\[\frac{y}{x+y}\%\]Does that make sense to you? It's just the mass of the apple divided by the mass of all things in the bag.

Answer 8

@lgbasallote you satisfied?

Answer 9

the answer is b) benzene

Answer 10

Since... composition means ratio here..

mass of C (in the given compound) : mass of H (in given compound)

so

In \(\huge{C_8 H_8}\) we have :

12*8 : 8*1
96: 8 or 12:1
`12:1` ---->\( C_8 H_8 \)


now in C_6 H_6

12*6 : 6*1
`12 : 1`--> \(C_6 H_6 \)

Answer 11

it is same for both hence the answer will be b) benzene , \(C_6 H_6\)

You can check it easily by doing for all...

Answer 12

similarly doing for A) C) D) we get all as correct..

So according to me it must contain another option namely : ALL OF THESE ..

My process is correct (as per me) ... hence E) All of these.

Answer 13

@lgbasallote satisfied?

Answer 14

....i did say nevermind

Answer 15

ah yes so u got the soln??

Answer 16

it still boggles me though....why do you people tend to not answer the question directly? i ask a yes or no question....and you all reply answers unrelated to what i asked lol