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2001 - Written Paper - Q4(b) - HSN forum

# 2001 - Written Paper - Q4(b)

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### #1Ray

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Posted 30 May 2005 - 03:10 PM

The question is the volume of carbon dioxide was 240cm
calculate the number of molecules in this volume
(malor volume of carbon dioxide = 24litres

Do you use density to work this question and if so wher would you find it

### #2dfx

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Posted 30 May 2005 - 03:23 PM

1 mol = 24 l = 24,000 cm
x = 240 cm

x = 0.01 so 240 cm = 0.01 mol

1 mol of CO has 3 x 6.02 x 10 ^
so 0.01 mol = 18.06 x 10^

Somebody confirm.

### #3Ally

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Posted 30 May 2005 - 03:28 PM

dfx, have you done your calculations properly?

I get it to be 6.02 x 1021 molecules.

To the original poster: you don't use density for this calculation.

### #4YIC

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Posted 30 May 2005 - 03:35 PM

I think dfx tried to work out the number of atoms, but they are asking for molecules, so dfx you can just divide you final answer by 3 to get no. of molecules

### #5coolncleo

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Posted 30 May 2005 - 03:43 PM

QUOTE(ally @ May 30 2005, 03:28 PM)
dfx, have you done your calculations properly?

I get it to be 6.02 x 1021 molecules.

To the original poster: you don't use density for this calculation.

yeah i got 6.02 x 1021 molecules.

cause 24000 is = to 6.02 x 10 23 molecules

so

240 is = to 6.02 x 1021 molecules.

### #6dfx

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Posted 30 May 2005 - 03:44 PM

Yea ma bad, sorry peeps, multiplied it by 3 for the number of atoms.

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