Top Posters
Since Sunday
15
14
E
7
i
5
j
5
4
a
4
m
4
p
4
e
4
s
4
1
4

# An unknown hydrate of cobalt(II) cyanide, Co(CN)2 • XH2O, is heated to give 32.7

wrote...
Posts: 6434
Rep:
7 years ago
 An unknown hydrate of cobalt(II) cyanide, Co(CN)2 • XH2O, is heated to give 32.7 An unknown hydrate of cobalt(II) cyanide, Co(CN)2 • XH2O, is heated to give 32.7% water. What is the water of crystallization (X) for the hydrate?A) 2B) 3C) 4D) 6E) 10 Read 497 times 4 Replies
Replies
ElectricElectric
wrote...
Top Poster
Posts: 6430
Rep:
7 years ago
 .silent.boss

### Related Topics

wrote...
7 years ago
 Perfect!..Thank you so much for your support
wrote...
7 years ago
 My pleasure
 .silent.boss
wrote...
A month ago
 The game plan with these is to figure out the number of moles of H2O there are per mole of CaSO4. Start by assuming any quantity of CaSO4 X H2O.Assume 100.0 g of CaSO4 XH2O.20.9 % of that = 20.9 gThat is the mass of water.1 mole of water = 18.0 g20.9 g x 1 mol/18.0 g = 1.16 mol H2O100 % - 20.9 % = 79.1 % CaSO479.1 g is the mass of CaSO41 mole of CaSO4 = 40.1 + 32.1 + 4(16.0) = 136.2 g79.1 g x 1 mol / 136.2 g = 0.581 mol CaSO4Now calculate the ratio of mol H2O to mol CaSO41.16 / 0.581 = 2.00So X = 2