Search for notes by fellow students, in your own course and all over the country.
Browse our notes for titles which look like what you need, you can preview any of the notes via a sample of the contents. After you're happy these are the notes you're after simply pop them into your shopping cart.
Title: stoichiometry and percentage purity
Description: made easy calculation for beginners
Description: made easy calculation for beginners
Document Preview
Extracts from the notes are below, to see the PDF you'll receive please use the links above
STOICHIOMETRY AND PERCENT PURITY
Many samples of chemicals are not pure
...
Conversely, the percent purity of an
impure sample of a chemical of unknown percent purity can be determined by reaction with a pure
compound as in an acid-base titration
...
This latter approach, however, assumes
a 100% yield of the product
...
3Mg(OH)2
(a)
+
2H3PO4
H
Mg3(PO4)2
+
6H2O
Calculate the mass of Mg3(PO4)2 that will be formed (assuming a 100% yield) from the
reaction of 15
...
5% Mg(OH)2 with an excess of H3PO4
...
0 x 0
...
875 g
mass Mg3(PO4)2 =
13
...
3 g Mg(OH)2
x
1 mole Mg3(PO4)2
262
...
9 g Mg3(PO4)2
(b)
Calculate the mass of 88
...
mass Mg(OH)2 =
127 g Mg3(PO4)2 x
1 mole Mg3(PO4)2
262
...
3 g Mg(OH)2
1 mole Mg(OH)2
= 84
...
mass 88
...
49 g Mg(OH)2 x
100 g 88
...
5 g Mg(OH)2
= 95
...
568 g of the sample
required 38
...
6695 M H3PO4
...
45 mL H3PO4 x
3 moles Mg(OH)2
58
...
6695 mole H3PO4
x
x
1000 mL H3PO4
1 mole Mg(OH)2
2 moles H3PO4
= 2
...
Percent purity =
2
...
7%
2
Title: stoichiometry and percentage purity
Description: made easy calculation for beginners
Description: made easy calculation for beginners