Just for the record what is a whoosh in a Kjeldahl determination.
Calculate the M of the HCl.Information to do that is in the second paragraph.
mols HCl initially = M x L = ?
mols excess HCl = M x L = ?
mols HCl used by the NH3 = difference
grams NH3 = mols NH3 x molar mass NH3
Then %NH3 = (g NH3/mass sample)*100 = ?
The nitrogen content of a .2476 g sample of a protein was determined by the Kjeldahl method. The NH3 produced with the whoosh was distilled into exactly 50.00mL of HCl in the receiving flask, which was in excess of the amount required to capture the ammonia gas. The excess HCl that was left over required 32.76 mL of .1234 M NaOH for neutralization.
In a preliminary lab, the HCl in the receiving flask had been previously standardized by neutralizing exactly 25.00mL of it with 21.15 mL of the same .1234 M NaOH.
What was the weight % nitrogen in the protein sample?
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