[jwj11]

So I just wrote a quiz and I'm scratching my head because they were marked incorrect. Please check over my teacher's answer key. I have provided my solutions as well.

-Question1-
What is the mass of 1.02 x 10^6 mol of aluminun borate?

Aluminum Borate = AlBO3
Molar Mass = 26.98 + 10.81 + 3(16.00) = 85.79 g/mol
Given n = 1.02 x 10^6 mol

m = nM = (85.79 g/mol)(1.02 x 10^6 mol)
           = 87.5 10^6 g.

However my teacher's answer key states that the correct answer in grams is 4.69 x 10^8 g

-Question2-
Niels Bohr's Model of the Atom has been likened by chemists to

the planet Saturn. (answer key)
a house fly buzzing around a floating pea. (My Answer)

I have no idea how the planet Saturn is correct because the planet saturn and it's rings are based on gravity, whereas the Bohr model introduced the fact it is not gravity, but electrostatic forces that constitute an atom. As such I thought she was trying to make an analogy to this with a "a house fly buzzing around a floating pea"

Please give me your opinion on this question....

[Ak]

AlBO3 seems to be correct...i cant find anything wrong with it.

[macman104]

The Saturn makes sense because there are discrete orbitals that the various electron shells circle around the nucleus in according to bohr's model very much like the rings of saturn.  I think the question in general is kind of dumb as it's open to interpretation, but I personally don't think the house fly answer is nearly as correct as the saturn one.

If you say saturn is incorrect because of gravity, then I say the house fly is incorrect because I fail to see the significant electrostatic forces at work for that analogy.

Also, I agree on the AlBO3 question, your answer seems correct.

[Borek]

The Saturn makes sense because there are discrete orbitals that the various electron shells circle around the nucleus in according to bohr's model very much like the rings of saturn.  I think the question in general is kind of dumb as it's open to interpretation, but I personally don't think the house fly answer is nearly as correct as the saturn one.

If you say saturn is incorrect because of gravity, then I say the house fly is incorrect because I fail to see the significant electrostatic forces at work for that analogy.

At the same time Saturn implies precise position of electron inside of the atom, while buzzing fly seem to be everywhere at the same time, which fits reality much better Dumb question.

Also, I agree on the AlBO3 question, your answer seems correct.

At least numerically. I have no idea whether aluminum borate exists, and if so - what is its formula, but on the high school my first reflex would be to try AlBO₃ as well.

Assuming answer key is right, that gives molar mass of 460. A lot for compound made of light elements Al, B and O.

[AWK]

Concerning AlBO3?
Key answer is evidently wrong

[DrCMS]

A quick google search comes up with the following possible formula:

Al₄B₂O₉  mass ~274

2Al₂O₃·B₂O₃·3H₂O  mass ~ 328

Al₁₈B₄O₃₃ or 9Al₂O₃.2B₂O₃ mass ~ 1058

It seems not to be a well defined material, so a very poor choice for a quiz question. 

Tell your teacher to pick better questions in future.

[macman104]

At the same time Saturn implies precise position of electron inside of the atom, while buzzing fly seem to be everywhere at the same time, which fits reality much better Dumb question.

But the groundwork for bohr's model was the electron shells yes?  It wasn't really regarding the incertainty of the position of the electrons, which would make that consideration out of the scope of the question... (still dumb question, but hey debates are fun!)

At least numerically. I have no idea whether aluminum borate exists, and if so - what is its formula, but on the high school my first reflex would be to try AlBO₃ as well.

Agreed.  I just saw that the borate polyatomic ion is BO₃^-3.  I am going to assume in highschool chem that they are not going to worry about the complexes DrCMS listed and that they just learn a list of polyatomic ions to work with, so in this case AlBO₃ seems to be correct.  But still a dumb question.