42.35% Na, 16.59% B, 44.00% O ?
32.61% Na, 36.48% B, 30.91% O ?
22.9% Na, 21.5% B, 55.7% O ?
46.2% Na, 21.7% B, 32.1% O ?
22.85% Na, 21.49% B, 55.66% O ?
2006-12-01 23:38:43 · 5 answers · asked by ? 3 in Science & Mathematics ➔ Chemistry
1. assume 1 mole of substance
2. calculate formula mass
2 Na = (1 mol) x (22.99g/mol) x 2 = 45.98 g Na
4 B = (1mol) x (10.81g/mol) x 4 = 43.24 g B
7 O = (1 mol) x (16.00g/mol) x 7 = 112 g O
molar mass 45.98g + 43.24g + 112g = 201.22 g/mol
% composition is found by dividing the mass of each element by the total mass
% Na = (45.98g)/(201.22g) = 0.2285 or 22.85% Na
% B = (43.24 g)/(201.22g) = 0.2149 or 21.49% B
% O =(112g)/(201.22g) = 0.5566 or 55.66%
Checking
22.85% + 21.49% + 55.66% = 100.00%
2006-12-02 00:32:38 · answer #1 · answered by rm 3 · 1⤊ 0⤋
Google is a student's best friend.
Try the link at the bottom of my post to see a list of very helpful websites that will guide you through this chemistry problem step by step.
Good luck!
2006-12-01 23:56:48 · answer #2 · answered by Jas 2 · 0⤊ 0⤋
525 600 minutes
2006-12-01 23:41:08 · answer #3 · answered by Anonymous · 0⤊ 2⤋
22.85% Na, 21.49% B, 55.66% O
2006-12-01 23:49:54 · answer #4 · answered by Anonymous · 0⤊ 0⤋
This may help!
2006-12-01 23:45:32 · answer #5 · answered by J. Charles 6 · 0⤊ 1⤋