What is a mole, what does it mean? help

Watch
Phantomx60
Badges: 9
Rep:
?
#1
Report Thread starter 4 years ago
#1
Need help undertsanding what a mole is , it's confusing me so much for some reason, could someone please explain this to me , thanks
0
reply
username1560589
Badges: 20
Rep:
?
#2
Report 4 years ago
#2
(Original post by Phantomx60)
Need help undertsanding what a mole is , it's confusing me so much for some reason, could someone please explain this to me , thanks
It's a small mammal that lives underground and eats worms.

Or Avagadro's number of things(can be molecules, atoms or whatever). One mole of atoms has approximately 6.022\times 10^{23} atoms.
3
reply
Phantomx60
Badges: 9
Rep:
?
#3
Report Thread starter 4 years ago
#3
(Original post by morgan8002)
It's a small mammal that lives underground and eats worms.

Or Avagadro's number of things(can be molecules, atoms or whatever). One mole of atoms has approximately 6.022\times 10^{23} atoms.
Yes but why in equations do teachers say 1 mole of an element and 1 mole of another element will result in 1 mole of a product , eg Mg + O > MgO
0
reply
Absent Agent
Badges: 21
Rep:
?
#4
Report 4 years ago
#4
(Original post by Phantomx60)
Yes but why in equations do teachers say 1 mole of an element and 1 mole of another element will result in 1 mole of a product , eg Mg + O > MgO
This is because one mole represents the number of atoms in the reactants but it represents the number of molecules in the products.
0
reply
username1560589
Badges: 20
Rep:
?
#5
Report 4 years ago
#5
(Original post by Phantomx60)
Yes but why in equations do teachers say 1 mole of an element and 1 mole of another element will result in 1 mole of a product , eg Mg + O > MgO
It should be Mg + \frac{1}{2}O_2 \rightarrow MgO.

What Mehrdad said.
0
reply
Absent Agent
Badges: 21
Rep:
?
#6
Report 4 years ago
#6
(Original post by Phantomx60)
Yes but why in equations do teachers say 1 mole of an element and 1 mole of another element will result in 1 mole of a product , eg Mg + O > MgO
Just to correct myself a bit as I didn't pay much attention to the equation. In the reactants, one mole of Mg does indicate the number of Mg atoms but not when dealing with O_2, but we halved the number of molecules of O_2 as this would be equal to one mole of O atoms. However, on the products, MgO has a giant ionic structure and so we cannot regard MgO as either atoms or molecules, but one mole of MgO represents one mole of O and Mg ions within the structure.
Hope this makes


Mg + \frac{1}{2}O_2 \rightarrow MgO.
0
reply
Absent Agent
Badges: 21
Rep:
?
#7
Report 4 years ago
#7
(Original post by Randall13)
It is an animal that lives in a burrow underground.
I'm not really sure if you're joking but the original poster means the Avogadro's constant as suggested in their second post.
0
reply
Phantomx60
Badges: 9
Rep:
?
#8
Report Thread starter 4 years ago
#8
(Original post by Randall13)
It is an animal that lives in a burrow underground.
seriously just stop with that -_-
1
reply
Phantomx60
Badges: 9
Rep:
?
#9
Report Thread starter 4 years ago
#9
(Original post by Mehrdad jafari)
Just to correct myself a bit as I didn't pay much attention to the equation. In the reactants, one mole of Mg does indicate the number of Mg atoms but not when dealing with O_2, but we halved the number of molecules of O_2 as this would be equal to one mole of O atoms. However, on the products, MgO has a giant ionic structure and so we cannot regard MgO as either atoms or molecules, but one mole of MgO represents one mole of O and Mg ions within the structure.
Hope this makes


Mg + \frac{1}{2}O_2 \rightarrow MgO.
It's kind of making sense but I'm still not sure tbh, any other way of explaining it? thanks for helping btw.
0
reply
Absent Agent
Badges: 21
Rep:
?
#10
Report 4 years ago
#10
(Original post by Phantomx60)
It's kind of making sense but I'm still not sure tbh, any other way of explaining it? thanks for helping btw.
Consider a different reaction:

2H_2 + O_2 \rightarrow 2H_2O.

Here we are dealing with molecules only but if you look at the both sides of the reaction, there are 3 moles and 2 moles of molecules on left hand side and on the right hand side of the reaction respectively.
Your confusion was that how the number of moles is not equal on the both sides of the reaction. Now consider 2 moles of H2 and 1 mole of O2 just as on the left hand side of the reaction. A molecule of water, H2O, contains a hydrogen molecule and one oxygen atom. This means that to make 2 moles of water, as on the right hand side of the reaction, we need 2 moles of hydrogen molecules (or 4 moles of hydrogen atoms as 2 moles of water will contain 4 moles of hydrogen atoms), and one mole of oxygen molecules. But if we were to break down the molecules on the both sides of the reaction we would get equal number of atoms from both sides.

H_2  \rightarrow 2H.
0
reply
X

Quick Reply

Attached files
Write a reply...
Reply
new posts
Back
to top
Latest
My Feed

See more of what you like on
The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

Personalise

Current uni students - are you thinking of dropping out of university?

Yes, I'm seriously considering dropping out (94)
13.78%
I'm not sure (32)
4.69%
No, I'm going to stick it out for now (214)
31.38%
I have already dropped out (16)
2.35%
I'm not a current university student (326)
47.8%

Watched Threads

View All