# chemistry unit 2

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#1
An aqueous solution of calcium hydroxide contains calcium ions and
hydroxide ions.
(i) How many moles of ions are there in one mole of calcium hydroxide?
(ii) How many moles of electrons are there in one mole of hydroxide ions?
I worked out the answer for part (i) which is 3
for part (ii) will we use Avogadro's constant? what should my first step be? I'm not quite sure how to attempt it...
0
1 year ago
#2
OH-
Oxygen 8 electron
Hydrogen 1 electron
Minus sign so another electron
Total 10 electron
Avogadro constant 6.02x10^23 times 10 which is 6.02x10^24
Btw how r u😊
1
#3
(Original post by Ailurophile03)
OH-
Oxygen 8 electron
Hydrogen 1 electron
Minus sign so another electron
Total 10 electron
Avogadro constant 6.02x10^23 times 10 which is 6.02x10^24
Btw how r u😊
just checked the marking scheme...it just says 10 ..THANKYOU!
I can't wait for alevels to be over. I'm repeating units 2 and 3 of chem cuz I didn't get a good grade. exams gonna start this Tuesday. soo not well. I feel like hibernating.
I finished my nyu application a few days ago which took a lot of time.
I'm so happy to hear from u! hows it going at ur end?
0
#4
(Original post by Ailurophile03)
OH-
Oxygen 8 electron
Hydrogen 1 electron
Minus sign so another electron
Total 10 electron
Avogadro constant 6.02x10^23 times 10 which is 6.02x10^24
Btw how r u😊
If it said 2 moles would the answer be 20?
0
1 year ago
#5
(Original post by : ).)
If it said 2 moles would the answer be 20?
IF... then yes.
1
1 year ago
#6
(Original post by : ).)
just checked the marking scheme...it just says 10 ..THANKYOU!
I can't wait for alevels to be over. I'm repeating units 2 and 3 of chem cuz I didn't get a good grade. exams gonna start this Tuesday. soo not well. I feel like hibernating.
I finished my nyu application a few days ago which took a lot of time.
I'm so happy to hear from u! hows it going at ur end?
Oh I’m kinda confused now. Why is the ans only 10
I was supposed to give my retakes in Jan but due to some issues I can’t.
I’ll be doing it along A2 in may😕.
I’m good thank u. How r u? Btw happy new year ❤️.
0
1 year ago
#7
(Original post by Ailurophile03)
Oh I’m kinda confused now. Why is the ans only 10
I was supposed to give my retakes in Jan but due to some issues I can’t.
I’ll be doing it along A2 in may😕.
I’m good thank u. How r u? Btw happy new year ❤️.
Draw a dot and cross diagram for one OH- ion. You'll see (assuming you, for a change, include the inner shell electrons).
0
1 year ago
#8
(Original post by Pigster)
Draw a dot and cross diagram for one OH- ion. You'll see (assuming you, for a change, include the inner shell electrons).
I mean don’t we have to multiply with Avogadro constant to find The number of electrons
0
1 year ago
#9
(Original post by Ailurophile03)
I mean don’t we have to multiply with Avogadro constant to find The number of electrons
The answer is 10 moles of electrons.
That could be written as 6.02x10^24 electrons, but there's no reason to do that, especially as the question asks 'how many moles'.
0
1 year ago
#10
(Original post by Trumbles)
The answer is 10 moles of electrons.
That could be written as 6.02x10^24 electrons, but there's no reason to do that, especially as the question asks 'how many moles'.
Ohh
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