Length Measurements – Follow the Instructions in the Lab Manual and fill in your data in the tables provided.

Data Table 1 – Length measurements

|Object |Length (cm) |Length (mm) |Length (m) |

|CD or DVD |12.00 |120.0 |.1200 |

|Key |6.10 |61.0 |.0610 |

|Spoon |16.00 |160.5 |.1605 |

|Fork |20.20 |201.5 |.2015 |

|Water |Temperature (oC) |Temperature (oF) |Temperature (K) |

|Hot from Tap |39.5 |103.1 | |

|Boiling | 102 |215.6 |375 |

|Boiling for 5 minutes |102 |215.6 |375 |

|Cold from Tap |22 |71.6 |295 |

|Ice water – 1 minute |4.5 |40.1 |277.5 |

| |2 |35.6 |275 |

|Ice water – 5 minutes | | | |

Data Table 2- Temperature Measurements

Data Table 3- Mass Measurements

|Object |Estimated Mass (g) |Actual mass (g) |Actual mass (kg) |

|Pen or Pencil |3 |5.6 |.0056 |

|3 Pennies |6 |7.5 |.0075 |

|1 Quarter |5 |5.7 |.0057 |

|2 qtrs, 3 dimes |20 |18.2 |.0182 |

|3 qtrs, 1 dime, 5 pennies |30 |31.9 |.0319 |

|Key |3 |9.8 |.0098 |

|Key, 1 qtr, 4 pennies |16 |25.5 |.0255 |

Data Table 4 – Liquid Measurements

| |Mass A |Mass B |Mass A-B | | |

|Magnet |4.7 |8.0 |9.0 |1 |4.7 |

|Metal Bolt |8.0 |8.0 |9.3 |1.3 |6.15 |

Data Table 7 – Archimedes Method

|Object |Mass (g) |Mass Displaced Water |Vol Displaced Water |Density (g/mL) |

| | |(g) |(mL) | |

|Magnet |4.6 |.9 |.9 |5.11 |

|Metal Bolt |8.0 |1.1 |1.1 |7.27 |

Data Table 8 – Initial Concentration

|Chemical |Mass (g) |Molecular Weight |Moles in volumetric |Total vol (L) |Molarity (mol/L) |

| | |(g/mol) |flask | | |

|Sugar (C12H22O11) |8.0 |342.19 |.023 |.025 |.920 |

Data Table 9 – Dilution Series

Dilution |Volume (mL) |Mass (g) |Density (g/mL) |Initial Concentration (M) |Volume Transferred (mL) |Final Conc (M) | |0 |25 mL |27.6 |1.10 | |0 mL |.920 | |1 |25 mL |25.1 |.996 |.920 |2.5 mL |.092 | |2 |25 mL |24.5 |.980 |.092 |4.5 mL |.017 | |3 |25 mL |24.5 |.980 |.017 |3 mL |.002 | |4 |25 mL |24.7 |.988 |.002 |6 mL |.00048 | |

Questions

A. Water boils at 100oC at sea level. If the water in this experiment did not boil at 100oC, what could be the reason?

B. While heating two different samples of water at sea level, one boils at 102oC and one boils at 99.2loC Calculate the percent error for each sample from the theoretical 100.0oC.

C. An unknown rectangular substance measures 3.6 cm high, 4.21 cm long, and 1.17 cm wide. If the mass is 21.3 g, what is this substance’s density in g/mL?

D. A sample of gold (Au) has a mass of 26.15 g. Given that the theoretical density is 19.30 g/mL, what is the volume of the gold sample?

E. What would happen if you dropped the object into the beaker while using the Archimedes’ principle method instead of submerging the object?

F. How did the magnet’s density measurement using the Archimedes’ Principle compare to the density measurement using the calculated volume? Which method might be more accurate? Why?

G. You are given a small piece of gold colored material and want to determine if it is actually gold. Using the Archimedes’ Principle you find that the volume is 0.40 cm3 and the mass is 6.0 g. What conclusions can you reach from your simple density analysis?

H. How would you prepare 10 mL of a 0.250 M HCl solution if 1 M HCl was available? How much 1 M HCL is needed? How much distilled water is used?

I. From the Excel chart of molarity vs density, what was the relationship between the molarity of the sugar solution and the density of the sugar solution?

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Sarah South

The difference in atmospheric pressure. If the pressure is less the water will boil at a lower temperature and vice versa.

Sample 1: (100-102)/100=2% error

Sample 2: (100-99.2)/100=.8% error

D=21.3/17.7=1.2 g/ml

V=1.35

The scale would measure the mass of the object instead of the displaced mass of water.

The density on the Archimedes method was slightly higher. The calculated method might be better because the ruler is more accurate and it’s easier to measure that way as oppose to submerging it while trying to read the value.

The density of the object is 15 g/ml. It might be gold but probably not pure gold.

The greater the Molarity, the greater the density.