Copper (II) Sulfate Crystals:
Before: - small (sand grain like) blue pieces with some white pieces
During: - a light blue rim forms around the edges of the crystals
- light blue rim spreads closer towards center
- blue crystals completely light blue
- white rim forms around edges, moves closer towards center
- light blue crystals completely white
After: - broken up into solid-like pieces
- light green on powder/crystals on bottom
Calculations:
Evaporating dish: 50.04g
Watch glass: 57.67g
Dish with Copper (II) Sulfate Crystals: 59.38g
Dish with CuSO4 crystals after cooling: 56.03g
1) 59.38g - 50.04g = 9.34g CuSO4
56.03g - 50.04g = 5.99g CuSO4
(9.34g - 5.99g = 3.35g)
3.35g/9.34g = 35.87% water lost
2) 35.87 - 36.08 = 0.0058 = 0.58% error
36.08
3)
= 0.06 mol CuSO4
0.06 = 1
= 0.19 mol H2O
0.06 = 3 (X=3)
CuSO4 ∙ 3H2O
Excellent job except that 0.19/0.06 = 6. You were thinking 18/6 which would be 3. That extra decimal place changes the answer. 18/20
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