How can I explain things better?

[tuahaa]

Well, I just did my science homework and I feel that my answers lack the proper language that I need to show I understand a topic while still answering the question properly. I'm in middle school.

For example (quoted from my science worksheet):

How is electronic configuration of an atom related to its period and group number?

(A whole paragraph is written under this and then crossed out because I wasn't satisfied with it. I wrote a slightly better one under it)

The electronic configuration of an atom relates to its group and period as the number of shells an atom possesses determines its period, while the number of electrons in its outermost shell determines the group.

And also, can anyone tell me if this makes sense (bold words are not in the actual text):

Question 10. The size of the atoms should increase as we move down a group. Explain why this could be logically expected.

As elements with a larger atomic number (or mass number) have more nucleons and electrons, they are of a larger size. (hard to write bit--->) Elements of the same group also arranged in this way. Also, atomic shells can only hold a specific number of electrons, so more must be created and hence expanding the size of the atom (lol, this is totally messed up. This should go before the last sentence and should be rephrased)

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I think I should do this all over again... might print it out on a separate sheet. Thank God this is just homework, if it was a test paper I would be ruined. I don't know what happened to me, I got an A+ on my science report and yet I can't do a task like this.

PS. There are worse answers for other questions which are not mentioned here. I need some help though

[Bachstelze]

Question 10. The size of the atoms should increase as we move down a group. Explain why this could be logically expected.


Here's how I would put it: if you move down a period, since the period is related to the the number of populated electronic shells, you have more pupulated shells. Therefore, you have more electrons. Therefore, since matter is electrically neutral, you need more nucleons to compensate. More nucleons = bigger atom.

[NoaHall]

Shelves ? Shells is what I would use.

[Bachstelze]

Shelves ? Shells is what I would se.

Is the fact that I've been awake for more than 24 hours straight an excuse? :p

[Regenweald]

Is the fact that I've been awake for more than 24 hours straight an excuse? :p

Definitely :) had me wondering there...

[tuahaa]

Here's how I would put it: if you move down a period, since the period is related to the the number of populated electronic shells, you have more pupulated shells. Therefore, you have more electrons. Therefore, since matter is electrically neutral, you need more nucleons to compensate. More nucleons = bigger atom.

Thats got too much 1st person language. I rewrote the answer to this anyhow, this is what I got:

10. The size of the atom should increase as we move down a group. Explain why this could be logically expected.

As elements with a higher atomic number (or mass number) have more nucleons, it is logical for the respective atoms to have a bigger size. If an atom has a large atomic number, it will also have more neutrons and more electrons than the atoms with less protons. This means there is a bigger nucleus and more shells, hence the total atomic size is larger, even if it has a smaller mass.

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Thanks for the answer though, I'm glad somebody is helping me out. Please feel free to help me improve my answer... well, anyway, I've got no homework for the weekend (weekend starts on friday here), time to listen to some music