A sample of 0.3220 g of an ionic compound containing the bromide ion (Br-) is dissolved in water and treated with an excess of AgNO3. If the mass of the AgBr precipitate that forms is 0.6364 g, what is the percent by mass of Br in the original compound?
2007-10-01 10:06:18 · 4 answers · asked by ws 3 in Science & Mathematics ➔ Chemistry
Net reaction
Ag+ + Br- = AgBr
1. find the number of moles of AgBr
.6364g/molar mass of AgBr = X
2. Since the reaction stoichimetry is 1Ag to 1Br, X moles of AgBr, must've required X moles of Br to begin with
So unknown must've had X * mass number of Br = Y grams of Br
3. Find % by diving Weight in grams by Total weight of the ionic compound
% Br = Y / .3220 * 100 = Your answer
2007-10-01 10:15:36 · answer #1 · answered by Jared 4 · 0⤊ 0⤋
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2007-10-01 10:17:07 · answer #2 · answered by catteyes 2 · 0⤊ 0⤋
I answered this question before. Is it possible that you asked it in the wrong way, again?
2007-10-01 10:11:20 · answer #3 · answered by steve_geo1 7 · 0⤊ 1⤋
.3144, i think thats the answer, im also taking chem but we didn't get up to that stuff yet.
2007-10-01 10:09:06 · answer #4 · answered by Anonymous · 0⤊ 0⤋