# aamc chem question pack #23

#### nostra_damus

2+ Year Member
Can somebody explain this to me please? I'm still a little confused why the answer isn't A. Thanks!

#### Attachments

• Screen Shot 2017-08-01 at 6.45.46 PM.png
371.1 KB · Views: 74
1 user

#### nostra_damus

2+ Year Member
Sorry realized I cut off the question part

#### Attachments

• Screen Shot 2017-08-01 at 6.52.36 PM.png
21.7 KB · Views: 30

#### aldol16

5+ Year Member
What part don't you get? It's a stoichiometry problem - the only caveat is that instead of having A + B ---> AB, you have n as coefficients. So let's make it more concrete by picking numbers. We'll use 2 to keep it simple - so you're making a dimer. 2 CDP ---> (CP)2 + 2 HPO4. What's the ratio of polymer (the dimer in this case) to HPO4? Well, it's 1/2. You can keep repeating this exercise - with n = 3, you'll get 1/3; with n = 4, you'll get 1/4 and so on. So the ratio of polymer to HPO4 can be obtained by the ratio 1/n.

1 user

2+ Year Member
What part don't you get? It's a stoichiometry problem - the only caveat is that instead of having A + B ---> AB, you have n as coefficients. So let's make it more concrete by picking numbers. We'll use 2 to keep it simple - so you're making a dimer. 2 CDP ---> (CP)2 + 2 HPO4. What's the ratio of polymer (the dimer in this case) to HPO4? Well, it's 1/2. You can keep repeating this exercise - with n = 3, you'll get 1/3; with n = 4, you'll get 1/4 and so on. So the ratio of polymer to HPO4 can be obtained by the ratio 1/n.

Is that because even though there's multiple subunits, it's just 1 mole?

This thread is more than 2 years old.

Your message may be considered spam for the following reasons: