DAT testing questions + gen chem question

[kov82]

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1)so in the Kaplan BB it says you can mark any questions and go back and review, its a stupid question but I'm guessing theres no 2 or 5 bonus minutes to review marked material right? you only use the time you have left?

2)the clock for the science section is all in one or the three subjects each have a clock? (I would prefer each having its own timer)

3)what info is missing from the table of elements they provide? is everything there that you would find in a table of elements in a chemistry textbook?

4)for group 6B on the table of elements I said the valence configuration is s^2 d^4 but the kaplan flash card says s^1 d^5 I see that it still comes out to 6 e- but is this a special case or a typo? if its a special case are there any others?

 

[pbure9]

1)so in the Kaplan BB it says you can mark any questions and go back and review, its a stupid question but I'm guessing theres no 2 or 5 bonus minutes to review marked material right? you only use the time you have left?

2)the clock for the science section is all in one or the three subjects each have a clock? (I would prefer each having its own timer)

3)what info is missing from the table of elements they provide? is everything there that you would find in a table of elements in a chemistry textbook?

4)for group 6B on the table of elements I said the valence configuration is s^2 d^4 but the kaplan flash card says s^1 d^5 I see that it still comes out to 6 e- but is this a special case or a typo? if its a special case are there any others?

1) I'm pretty sure you dont get extra bonus time to go over what you marked. Only the time you are given.
2) I'd like to know this too...
3) Everything that you need is there. Elements, atomic masses and atomic numbers
4) This isn't a typo. 6B Transition state elements will put 1 electron from their s orbital into their d orbital as its the most stable configuration. Watch out with silver and copper as well. They're not s^2 d^9, but s^1 d^10

 

[peyman2002]

I think one big block of 90 min for all 3 sections

 

[cyrano]

4) As pbure said the transition metals can be tricky. The electrons wanted to fill at least half of every orbital. This happens when you have 6 valence electrons there. If you think about it makes sense for two reasons. 1) There's a ton of room in that completely empty orbital so why not move in there? and 2) The orbitals are relatively equal in energy so it's not like the electron is having to increase in energy to inhabit that d orbital.

 

[bigstix808]

1)so in the Kaplan BB it says you can mark any questions and go back and review, its a stupid question but I'm guessing theres no 2 or 5 bonus minutes to review marked material right? you only use the time you have left?

2)the clock for the science section is all in one or the three subjects each have a clock? (I would prefer each having its own timer)

3)what info is missing from the table of elements they provide? is everything there that you would find in a table of elements in a chemistry textbook?

4)for group 6B on the table of elements I said the valence configuration is s^2 d^4 but the kaplan flash card says s^1 d^5 I see that it still comes out to 6 e- but is this a special case or a typo? if its a special case are there any others?

1) no bonus time
2) 90 min for all science topics (pace yourself)
3) you get atomic #, atomic weight, atomic symbol
4) prob a special case - go with what you've been taught

 

[cyrano]

Alright, just ignore my previous post. While it is correct, it doesn't give you a hard and fast rule to go by. So I thought of two rules to guide you on the two columns (4th transition metal and 9th transition metal) that are exceptions to general electron filling,

1) If by bumping up one S electron you can half fill each of the D orbital (1 electron apiece) than do it.

i.e. Cu is
[Ar] 4s13d10

and

2) If you can fill all the D orbitals with two electrons by bumping up a single S electron than do that.

i.e. Cr is
[Ar] 4s13d5

Hurray!! Hope this makes sense. If not PM me or just post on here and I'll check back.

 

[brightsmiles9]

You don't get any extra time to go back to the mark questions, you basically use up the time you have leftover to check over those questions. For the science section its 90 minutes for all the sections combined, so you can finish one section faster than the rest and use up the minutes in another section if you want.

 

[tdkyun]

Just memorize these 5. Cr, Mo, Cu, Ag, Au.
They will all pull an electron from their s shell to stabilize their d shell. (full or half full)
So, for example, Ag e- config will be [Kr] 5s1 4d10 (s,d shells are both half full, which is more stable than having 4d9) instead of 5s2 4d9

 

[MaverickPreDent]

Some helpful info here. Thanks =D

 

[kov82]

So on the topic of configurations, for Eu I put [xe] 6s^2 4f^6 5d^1 to get 63 which was in the solutions book BUT it stipulated that the answer I got was "using only the periodic table" but that "the actual electron configurations are: Eu: [Xe] 6s^2 4f^7 " so what gives? which is correct on the DAT????? and does the pattern on "the actual configuartion" apply to all the f block elements? I can memorize a pattern but can someone explain why there are two different answers and which I should always use?????