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[Redoctober]

I have a question about conversion (ppmv to ppmw) like below,

Moisture is measured by moisture analyzer in H2 gas.
The range is 0~ 2ppmv
So I want to conversion this range to ppmw

2ppmv= 2mol H2O / 10^6 mol H2
= [2mol H2O x 18g/mol] / [10^6mol H2 x 2g/mol] ( 18g/mol : H2O MW , 2g/mol : H2 MW)
=36g/2,000,000g
=18ppmw

So the range is 0 ~ 18ppmw

Is my understanding right?
Please give your opinion.

[wangyang]

I thought that a small revision on your calculation on this topic:
2ppmv= 2mol H2O / [(10^6-2 )mol H2 +2mol H2O]
= [2mol H2O x 18g/mol] /{ [(10^6-2)mol H2 x 2g/mol] +[2mol H2 x 18g/mol] } (18g/mol : H2O MW , 2g/mol : H2 MW)
=36g/2,000,032g
=17.9997ppmw