Density

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Part 1
Problem: How can you determine the density of water?
Hypothesis: If we measure 25 mL, 50 mL, 75 mL, and 100 mL of water, and measure all of these amounts on an three beam balance, then we can find the density of water using the density formula.
Procedure:
1. Clean and dry the pan on your balance.
2. Zero your balances.
3. Determine the mass of a 100 mL dry graduated cylinder. Record in Data Table I.
4. Measure the following volumes of water: 25 mL, 50 mL, 75 mL, and 100 mL. record the mass of the water and the graduated cylinder in the data table.
5. Record the mass of just the water.
6. Determine the density of the water for each volume. (D = M/V)
7. Determine the average density.
8. Make a graph showing Mass (g) versus Volume (mL) using a best fit line.

Data Table I

|Volume of Water |Mass of Water and |Mass of Water |Density of Water (D = |
| |Grad. Cylinder | |M/V) g/mL |
|O mL |98.20 | | |
|25 mL |127.00 |28.80 |1.152 grams/mL |
|50 mL |145.40 |47.20 |0.944 grams/mL |
|75 mL |172.50 |74.30 |0.991 |
|100 mL |196.00 |97.80 |0.978 grams/mL |
|Average density | | |1.02 grams/mL |
| |no |no | |
|% error |no |no |-2% |

Conclusion:
Answer the following questions and write a paragraph explaining your results.
1. Why was the density not the same for