Laboratory Techniques and Measurements
Lab 1 “Laboratory Techniques and Measurements”
A. Water boils at 100C at sea level. If the water in this experiment did not boil at 100 C, what could be the reason?
* We’re not at sea level; the pressure could be lower or higher.
B. While heating two different samples of water at sea level, one boils at 102C and one boils at 99.2C. Calculate the percent error for each sample from the theoretical 100C. (show your work)
* 1st Sample: 1.96% error * 2nd Sample: 0.81% error
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 grams per milliliter)?
* Volume= 3.6*4.21*1.17= 17.7g * Density= mass/volume= 21.3/17.7= 1.2g/mL * Density= 1.2g/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?
* Volume= mass/density= 26.15/19.30= 1.35mL * Volume= 1.35mL
E. What would happen if you dropped the object into the beaker while using the Archimedes’ Principle method instead of submerging the object?
* If the object was dropped into the beaker, the measurements would not be correct or accurate.
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?
* The calculated volume is more accurate than the Archimedes’ Principle because it may have a higher percentage of error.
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?
* Density= 6.0/0.40= 15g/cm3 * The small gold material can’t be gold because the density of solid pure gold is about 19.32 g/cm3.
H. How would you
A. Water boils at 100C at sea level. If the water in this experiment did not boil at 100 C, what could be the reason?
* We’re not at sea level; the pressure could be lower or higher.
B. While heating two different samples of water at sea level, one boils at 102C and one boils at 99.2C. Calculate the percent error for each sample from the theoretical 100C. (show your work)
* 1st Sample: 1.96% error * 2nd Sample: 0.81% error
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 grams per milliliter)?
* Volume= 3.6*4.21*1.17= 17.7g * Density= mass/volume= 21.3/17.7= 1.2g/mL * Density= 1.2g/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?
* Volume= mass/density= 26.15/19.30= 1.35mL * Volume= 1.35mL
E. What would happen if you dropped the object into the beaker while using the Archimedes’ Principle method instead of submerging the object?
* If the object was dropped into the beaker, the measurements would not be correct or accurate.
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?
* The calculated volume is more accurate than the Archimedes’ Principle because it may have a higher percentage of error.
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?
* Density= 6.0/0.40= 15g/cm3 * The small gold material can’t be gold because the density of solid pure gold is about 19.32 g/cm3.
H. How would you