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Chemistry Homework Help => AP Chemistry => Topic started by: Tsuanthony on September 29, 2009, 02:01:53 AM

Title: Solving Stoichiometry ..Calculations based on chemical equations..
Post by: Tsuanthony on September 29, 2009, 02:01:53 AM
can't really figure /sort this one out :(

so the given balenched equation

Na2SiO3 + 8 HF  ----> H2SiF6 + 2 NaF + 3H2O

how many grams of NaF form when 0.500 mol of HF react with excess Na2Sio3 ?

I think it's a limiting reagent problem someplace.. but not sure plz help asap
Title: Re: Solving Stoichiometry ..Calculations based on chemical equations..
Post by: uma on September 29, 2009, 09:40:12 PM
From equation
8moles of HF give 2 moles of NaF
Now number of moles of HF= 0.500
No of moles of NaF formed = 0.500  X 2/ 8 = 0.125
I have used the factor 2/8 to convert it to moles of NaF
Now you just need to multiply moles of NaF with its molarmass to get the answer.