# 5R question, # 24

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#### kimijohni

##### Member
10+ Year Member
5+ Year Member

How the heck do I do this question? Well, for any of you who can help, the question states as follows
" How many ML. of a 2M solution of Na2CO3 are required to produce 11.2 L of Co2 at STP. The equation they so shows a 1:1 ratio. Their explanation was not english to me so Im hoping someone can break it down for me easily.
Thanks

#### soulstress

##### New Member
10+ Year Member
At STP, 1 mol of any ideal gas is equal to 22.4 L in volume.

So 11.2 L of CO2 is equal to 0.5 mol, which equals 0.5 mol Na2CO3 as per the mol ratio. From that you should be able to answer it.

Hope that helps.

#### kimijohni

##### Member
10+ Year Member
5+ Year Member
Unfortunately, thats exactly where I got to and got stuck. If you know its .5 how do you do the math from there?
soulstress said:
At STP, 1 mol of any ideal gas is equal to 22.4 L in volume.

So 11.2 L of CO2 is equal to 0.5 mol, which equals 0.5 mol Na2CO3 as per the mol ratio. From that you should be able to answer it.

Hope that helps.

#### aung

##### Senior Member
10+ Year Member
5+ Year Member
Well if you know you need 0.5 mol Na2CO3 and you got a 2M solution Na2CO3, which is 2 mol/1 L, you can set up a proportion:

.5mol/ X liters = 2 mol/ 1 L (2M concentration)

X=.25 L= 250 mL

#### soulstress

##### New Member
10+ Year Member
Sorry about stopping at the mol ratio (that's the part that got me!). But yup, that's exactly what I did to find the answer too.

#### kimijohni

##### Member
10+ Year Member
5+ Year Member
Thanks guys,
I appreciated it, I hate when it so simple that you think it has to be more compicated then it sounds.
Thank you