Hi I have a lab for Chemistry I am struggling with. I have to do calculations given the following information 1.Mass of evaporating dish plus sample 26.57 g
2.Mass of evaporating dish 24.29 g
3.Mass of evaporating plus NaCl 68.66 g
4.Mass of evaporating dish 67.84 g
5.Mass of filter paper plus sand 37.69 g
6.Mass of filter paper 36.34 g
CALCULATIONS AND CONCLUSIONS
1.Calculate the mass of unknown mixture g

2.Calculate the mass of NaCl recovered g

3.Calculate the mass of sand recovered g

4.Calculate the percentage of NaCl in your unknown mixture %

5.Calculate the percent sand in your unknown mixture %

6.Calculate the total mass of sand and salt recovered g

7.Calculate the percent recovery of the components %
 

1.  2.28 g

2. 0.82 g

3. 1.35 g

4. 36 %

5. 59 %

6. 2.17 g

7. 95 %

Explanation:

Hello,

1. In this case, the mass of the unknown mixture is obtained by subtracting the mass of the dish plus sample and the mass of the dish:

m = 26.57 g- 24.29 g = 2.28 g

2. In this case, the mass of the NaCl recovered is obtained by subtracting the mass of the dish plus NaCl and the mass of the dish:

m = 68.66 g- 67.84 g = 0.82 g

3. In this case, the mass of the sand recovered is obtained by subtracting the mass of the filter paper plus sand and the mass of the filter paper:

m = 37.69 g- 36.34 g = 1.35 g

4. The percentage of NaCl is computed by considering its mass and the mass of the unknown mixture:

% NaCl = 0.82 g / 2.28 g * 100 % = 36 %

5. The percentage of sand is computed by considering its mass and the mass of the unknown mixture:

% sand = 1.35 g / 2.28 g * 100 % = 59 %

6. Here,we have to add the mass of NaCl and sand:

m = 0.82 g + 1.35 g = 2.17 g

7. Finally, the percent recovery is obtained by diving the total recovered mass by the total obtained mass of the mixture:

% recovery = 2.17 g / 2.28 g * 100 % = 95 %

Best regards.