Am I right? Calculate the mass percentage of water in the hydrate. Show the calculations. Sample 1 : 60.87% Mass of hydrate : 0.46g Mas of water : 0.28g Mass percentage of water in the hydrate = 0.28g/0.46g x 100 = 60.87% Sample 1 2 3 Calculations for sample 1 Mass of aluminum dish 1.24g 1.26g 1.24g - Mass of aluminum dish + Epsom salt 1.70g 1.94g 1.80g - Epsom salt, original (hydrated) mass 0.46g 0.68g 0.56g 1.70g – 1.24g = 0.46g Mass of aluminum dish + Epsom salt after heating 1.42g 1.62g 1.61g Epsom salt, heated (dehydrated) mass 0.18g 0.36g 0.37g 1.42g- 1.24g = 0.18g Mass of water 0.28g 0.32g 0.19g 0.46g – 0.18g = 0.28g Moles of magnesium sulfate 0.0015mol 0.0030mol 0.0031mol 0.18g x (1mol/120.37g)= 0.0015mol Moles of water 0.016mol 0.018mol 0.011mol 0.28g x (1mol/18.02g) = 0.016mol Ratio of moles water: moles of magnesium sulfate 32:3 18:3 11:3.1 0.016 : 0.0015= 32:3 Average Ratio
Am I right?
- Calculate the mass percentage of water in the hydrate. Show the calculations.
Sample 1 : 60.87%
Mass of hydrate : 0.46g
Mas of water : 0.28g
Mass percentage of water in the hydrate = 0.28g/0.46g x 100 = 60.87%
Sample |
1 |
2 |
3 |
Calculations for sample 1 |
Mass of aluminum dish |
1.24g |
1.26g |
1.24g |
- |
Mass of aluminum dish + Epsom salt |
1.70g |
1.94g |
1.80g |
- |
Epsom salt, original (hydrated) mass |
0.46g |
0.68g |
0.56g |
1.70g – 1.24g = 0.46g |
Mass of aluminum dish + Epsom salt after heating |
1.42g |
1.62g |
1.61g |
|
Epsom salt, heated (dehydrated) mass |
0.18g |
0.36g |
0.37g |
1.42g- 1.24g = 0.18g |
Mass of water |
0.28g |
0.32g |
0.19g |
0.46g – 0.18g = 0.28g |
Moles of magnesium sulfate |
0.0015mol |
0.0030mol |
0.0031mol |
0.18g x (1mol/120.37g)= 0.0015mol |
Moles of water |
0.016mol |
0.018mol |
0.011mol |
0.28g x (1mol/18.02g) = 0.016mol |
Ratio of moles water: moles of magnesium sulfate |
32:3 |
18:3 |
11:3.1 |
0.016 : 0.0015= 32:3 |
Average Ratio |
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