1 mol of paper - how much is that?

  • Context: Undergrad 
  • Thread starter Thread starter ecet
  • Start date Start date
  • Tags Tags
    paper
Click For Summary

Discussion Overview

The discussion revolves around the concept of how much paper can be produced from 1 mole of atoms, specifically focusing on the chemical composition of paper and the implications of using the mole as a unit of measurement in this context. Participants explore theoretical calculations related to the mass and number of A4 sheets that could be derived from a mole of cellulose, the primary component of paper.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant questions the chemical composition of paper and how it relates to calculating the mass of 1 mole of paper.
  • Another participant emphasizes the need to understand the definition of a mole and its implications for calculating quantities.
  • It is suggested that if paper is assumed to be made of 100% cellulose (C6H10O5), a rough estimate for the mass of a mole of cellulose could be calculated, leading to a figure of approximately 168 grams for a mole of cellulose molecules.
  • Further calculations indicate that if considering individual atoms in the appropriate proportions, the mass could be around 8 grams for a mole of cellulose.
  • One participant notes that cellulose is a polymer, which complicates the calculations since each molecule averages around 1000 monomer units, potentially increasing the weight of a mole of paper significantly.
  • Participants provide rough estimates for the weight of an A4 sheet of paper, with one suggesting it weighs about 5 grams.
  • There is acknowledgment that the calculations are approximate and depend on the exact composition of paper, which is not purely cellulose.

Areas of Agreement / Disagreement

Participants generally agree on the need to understand the chemical composition of paper and the implications of using the mole for calculations. However, there is no consensus on the exact mass or number of sheets that can be derived from a mole of atoms, as various assumptions and approximations are discussed.

Contextual Notes

The discussion highlights limitations related to the assumptions made about the composition of paper, the definition of the mole, and the variability in the molecular weight of cellulose. The calculations are based on simplified models and may not reflect the actual composition of paper.

ecet
Messages
3
Reaction score
0
My question is a bit chemically, but...
What's the atoms, what's makes the paper?
How many paper i get from 1 mol of atoms, what contains the paper?
How many grams, or pieces of A/4 size papers?
 
Physics news on Phys.org
Hi ecet. Welcome to PF.

Let's start with the mole (not 'mol'). Can you tell us what is your understanding of its definition? What does a 1 mole of something mean?
 
In order to know the mass of 1 mole of paper you first have to know the chemical composition of paper. Paper is a composite of various materials so it would be difficult to calculate.
 
Bandersnatch said:
Hi ecet. Welcome to PF.

Let's start with the mole (not 'mol'). Can you tell us what is your understanding of its definition? What does a 1 mole of something mean?

Oh, sorry, I'm from Hungary, and there it's mol, and I haven't read this word in Englis, so, yes, 1 mole of paper.
I meant, that how many paper can I get from 6x10^23 pieces of atoms? I know, it contains a lot's of type of atoms, maybe carbon, oxigen, hydrogen, ect...
If it were known (for me), that what types of atoms paper made of, and how many is the ratio of each other, than I maybe can calculate, that how much of the mass of the atoms, what I "use to build some paper from them".
I know, it's not a practical usefulness, but I've thinked about that, it's just theoretical :)
 
It's called 'mole' in English, but the SI unit symbol is 'mol', so it's easy to get confused. It's of little importance though.

O.k. So, you know that the mole is an amount of something.
In any definition of the mole you'll see that 1 mole of pure Carbon-12 atoms weights 12 grams (or, equivalently, 1 mole is as many entities as in 12g of C-12).
If we assume that paper is made 100% of cellulose (to make it simple), which in turn is made of carbon, hydrogen and oxygen: C6H10O5. That's 21 atoms per molecule, altogether weighing roughly the same as 14 Carbon-12 atoms.

So, if you were to ask 'how much paper I'd get from a mole of cellulose molecules', that'd be about 14*12=168 grams. If you were to ask how 'much paper from individual atoms, in appropriate proportions to make cellulose' that'd be 21 times less (since it's 21 atoms per molecule): 168/21=8 grams.

For comparison, a typical A4 sheet weighs about 5 grams.

These are rough numbers, since paper is not 100% cellulose, and its molecular weight in not exactly the same as 14 C-12 atoms, but the difference shouldn't be much.
If you care for more precision you can just research more exact composition and follow the same line of thinking.
 
An added difficulty is that cellulose is a polymer with each molecule averaging 1000 or so monomer units. This would increase the weight of a mole of paper by 1000 over that stated above.
 
Bandersnatch said:
It's called 'mole' in English, but the SI unit symbol is 'mol', so it's easy to get confused. It's of little importance though.

O.k. So, you know that the mole is an amount of something.
In any definition of the mole you'll see that 1 mole of pure Carbon-12 atoms weights 12 grams (or, equivalently, 1 mole is as many entities as in 12g of C-12).
If we assume that paper is made 100% of cellulose (to make it simple), which in turn is made of carbon, hydrogen and oxygen: C6H10O5. That's 21 atoms per molecule, altogether weighing roughly the same as 14 Carbon-12 atoms.

So, if you were to ask 'how much paper I'd get from a mole of cellulose molecules', that'd be about 14*12=168 grams. If you were to ask how 'much paper from individual atoms, in appropriate proportions to make cellulose' that'd be 21 times less (since it's 21 atoms per molecule): 168/21=8 grams.

For comparison, a typical A4 sheet weighs about 5 grams.

These are rough numbers, since paper is not 100% cellulose, and its molecular weight in not exactly the same as 14 C-12 atoms, but the difference shouldn't be much.
If you care for more precision you can just research more exact composition and follow the same line of thinking.

Based on your details, I tried to calculate the same way, and it's around your result: 7,7179... grams, what's around your result.
 

Similar threads

  • · Replies 42 ·
2
Replies
42
Views
3K
  • · Replies 40 ·
2
Replies
40
Views
8K
  • · Replies 14 ·
Replies
14
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
Replies
3
Views
2K
  • · Replies 2 ·
Replies
2
Views
1K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 16 ·
Replies
16
Views
1K
  • · Replies 5 ·
Replies
5
Views
2K