This is a limit test for chlorides.
1.0g of NaOH sample was dissolved in 5ml of deionized water, acidified with 4ml of concentrated nitric acid (65%) and diluted to 15ml with deionized water. (Test tube A)
10ml of 50ppm Standard NaCl solution was prepared. 5ml of water was added, followed by 1ml of dilute nitric acid. (Test tube B)
1ml of AgNO3 was added to each of the test tubes and compared for opalescence.
Can you explain why we need to add 4ml of concentrated nitric acid and how was the 4ml derived?
Ag ion reacts with strongly basic solution to produce a hydrated Ag2O sometimes simply written as Ag(OH)2. It's a dark brown/black gelatinous ppt when Ag ion is added to a basic solution. So the 4 mL HNO3 is to neutralize the NaOH and make sure the solution is acidic. HNO3 is used because neither HCl nor H2SO4 can be used; HCl for the chloride content and H2SO4 because of solubility concerns. 65% HNO3 is very close to 15 M and 4 mL of that is enough to neutralize all of the NaOH (about 1/40 = 0.025 moles) (4 mL of 15 M HNO3 is about 0.06 mols).
This is a limit test for chlorides. 1.0g of NaOH sample was dissolved in 5ml of deionized water, acidified with 4ml of dilute nitric acid and diluted to 15ml with deionized water. (Test tube A) 10ml of 50ppm Standard NaCl solution
This is a test for chlorides in NaOH sample. 1.0g of NaOH was dissolved in 5ml of distilled water, acidified with 4ml of dilute nitric acid and diluted to 15ml with distilled water. This mixture was poured into a test tube
Hi,there was an error with the procedure. 1.0g NaOH sample was dissolved in 5ml of water and acidified with 4ml of conc. nitric acid,not dilute nitric acid. This was then made up to 15ml with water.After acidifying with conc.
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NaOH(s)+ H2SO4(aq)=Na2SO4(aq) + H2O(l) Consider the unbalanced equation above.A 0.900 g sample of impure NaOH was dissolved in water and required 37.0 mL of 0.145 M H2SO4 solution to react with the NaOH in the sample. What was the
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Why 7ml of 10M HCl? Do I add 7ml of 10M HCl 1st slowly in ice bath, then slowly adjust the pH to 7 using 10M HCl? Then to dilute to 15ml in a graduated cylinder? Thanks Posted by candy on Tuesday, September 21, 2010 at 10:03am.
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