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I'll show you mine if you show me yours. :ninja:


...in other words, why don't you show us what you've drawn and we'll tell you if you're correct. Instead of us giving you the answers straight up. :smile:
Reply 2
(Correct me if its wrong please)

Is it something like this:

Akkuz
(Correct me if its wrong please)


Erm, Ca(OH)2 is ionic :smile:
Calcium's a metal so there'd be an Ionic bond ... :ninja:

EDIT: Aw crap, EierVonSatan beat me to it. :frown:
EierVonSatan
Erm, Ca(OH)2 is ionic :smile:


This.

You do two square bracets.

Like this
PeanutButterJellyTime
Like this


There is a covalent bond between the O and H, though.
EierVonSatan
There is a covalent bond between the O and H, though.


Its only A levels. :>.<: they don't care.
PeanutButterJellyTime
Its only A levels. :>.<: they don't care.


lol I bet they would :p:

Here is what it should look like.
EierVonSatan
lol I bet they would :p:

Here is what it should look like.


Edexcel isn't really picky. Other examining boards such as AQA and OCR can be at times.

BTW nice use of Colour :biggrin:
Reply 10
I'm on OCR ^^

I'm not sure where your blue electron came from, I drew this, I think it's the same?

EDIT: Apologies for the very scruffy writing.

EDIT2: After looking at it again, my OH bonds wouldn't have a negative charge...I think I understand now. The electron from Ca pairs with the oxygen and the other electron of oxygen bonds with hydrogen. But that wouldn't have a negative charge? Arghh, confused.
Woody.
I'm on OCR ^^

I'm not sure where your blue electron came from, I drew this, I think it's the same?

EDIT: Apologies for the very scruffy writing.

EDIT2: After looking at it again, my OH bonds wouldn't have a negative charge...I think I understand now. The electron from Ca pairs with the oxygen and the other electron of oxygen bonds with hydrogen. But that wouldn't have a negative charge? Arghh, confused.


I think its because there are 3 different types of atom's (Ca, H and O), hence, you must indicate that they have distinct electrons.

Correct me if i'm wrong EierVonSatan :wink:
Reply 12
Yeah, thanks. I do understand the blue part now, but I'm rather confused on the edited areas
PeanutButterJellyTime
Edexcel isn't really picky. Other examining boards such as AQA and OCR can be at times.

BTW nice use of Colour :biggrin:


Thanks :biggrin:

I would be that picky :p:

Woody
Yeah, thanks. I do understand the blue part now, but I'm rather confused on the edited areas


Okay in ionic compounds metals donate electrons to non-metals, so the outer two electrons of calcium have been donated to the OH's, hence they have 1 blue electron and a negative charge each. This leaves Ca with a 2+ charge and a full outer shell.

Oxygen has six electrons (red) + 1 from Ca (blue) and is sharing one of it's electrons with the hydrogens (green). Hope that helps :smile:
Reply 14
EierVonSatan
Erm, Ca(OH)2 is ionic :smile:


ohh yeah, haha. cheers. :banghead:
Reply 15
EierVonSatan
lol I bet they would :p:

Here is what it should look like.



yeh but they ask you to draw a 'dot and cross diagram' not a ' 3 different colour dots diagram', so what would be the best way to answer this question?
Reply 16
EierVonSatan


Oxygen has six electrons (red) + 1 from Ca (blue) and is sharing one of it's electrons with the hydrogens (green). Hope that helps :smile:



so basssiicaaally

Ca(OH)2 has a mixture of ionic and covalent bonding

covalent bonding between the Oxygen and Hydrogen, and ionic between Ca and O( causing the OH ion to have a negative charge)

am i right or am i right?
sonic23
so basssiicaaally

Ca(OH)2 has a mixture of ionic and covalent bonding

covalent bonding between the Oxygen and Hydrogen, and ionic between Ca and O( causing the OH ion to have a negative charge)

am i right or am i right?


You're right...
Reply 18
Yeah, I think I do get it now, cheers :smile:

Could you verify that my drawing of it is correct? Thanks.
Woody.
Yeah, I think I do get it now, cheers :smile:

Could you verify that my drawing of it is correct? Thanks.


You need to show that the extra electron on the oxygen doesn't originate from the oxygen somehow, otherwise it's fine :smile: