Glycerin Lab Report

Please explain the purpose of this lab. Include in your explanation the major concepts you learned and any safety concerns associated with the lab.

them to any scientific changes. The mass of the gummy bear in the bag before the

In this experiment, the precision of percent by mass of sodium carbonate was decent. It seemed to be consistent, although we seemed to have an outlier in our fifth trial. I believe this was due to human error of adding too much vinegar to this graduated cylinder. The accuracy of our results was decent in comparison to the rest of the class’s data, but our results were on the higher end compared to the averages of the class data, though not too high to be considered

There are several sources of error to this experiment due to random and systematic errors. The only source of random error was the measurement that we took through the graduated cylinder which was only accurate to the nearest 1%. We took the largest error from this one percent, which was +/- 3. The largest relative error this yielded was only 3%, so this did not affect how precise this experiment was too much. We can still make this more precise by making the masses of the water larger. For example if we started the masses at 300mL and went up by 50mL, the largest error this would yield would be 2% due to the largest error being +/- 5. This would cause smaller errors in the amount of water.

For example, how to physically find the density of an object by finding their mass with a balance and finding the object's volume using the method water displacement. The purpose of the experiment was to find out which metal is used to create post 1982 pennies. Pre-1982 pennies were made out of copper but then the metal used for making pennies changed. The metal used to create pre-1982 pennies was copper. Since the metal used to make pennies changed the density of post-1982 changed.

CHM130 Lab 6 Exploring Density Name A. Data Tables Place your completed Data Tables here Part IIIa (3 points) Volume of water in graduated cylinder (mL)10 mlMass of rubber stopper (g)11.15Volume of water and rubber stopper (mL)16.5 Part IIIb (6 points) Volume of water in graduated cylinder (mL)20Mass of iron nail (g)3.66Volume of water and iron nail (mL)20.5 Part IV (20 points) Type of Aluminum FoilMass (g)Length (cm)Width (cm)Volume (cm3)Thickness (cm)Regular.63g15 cm 10.02 cm.21 cm3.0014 cm Heavy Duty.97g15 cm10.01 cm .36 cm3.0024 cm B. Follow Up Questions Show all work for questions involving calculations. Part I Use the concepts/vocabulary of density to explain why the liquids formed layers in Part I of the procedure. (8 pts)

5. The degree of precision was to 3 significant figures obtained with the spectrophotometer. The major source of error in our experiment was not calibrating the spectrophotometer with distilled water.

I found out that both of my experiments were off by 0.46 and 0.13 but were remotely

In this lab, the molar mass of a volatile liquid is determined based on its physical properties in the vapor state. In order to calculate the molar mass, the mass, temperature, pressure, and volume is measured independently and then converted to the correct units. Sample C was obtained at the beginning of the experiment, which was later informed to be ethanol. Based on the calculations made, the molar mass of the volatile liquid was 95.9 g/mol. However, compared to the known value of 46.1 g of ethanol, the value measured had a 108% error. Unfortunately, this was a very big percent error and may have been caused by incorrectly measuring the volume of the gas. Using the ideal gas law, the molar mass of a volatile compound was calculated in order

Purpose: Weighing objects. Figuring out the density with an object by calculated volume and Archimedes’ Principle.

However, this is inconsistent with what we have been taught and with what is written in the textbook. Since the textbook is a more reliable source of information, I must conclude that the reason for this difference in results may be attributed to error on the part of the students conducting the experiment.

All of the tests were fair enough. Our first experiment was ⅓ (667 milliliters) and that test went very well. Our second experiment was ½ (1000 milliliters),⅓ (667 milliliters), and ¼ (500 milliliters). We tested all three bottle and it came down to two water amounts which were ½ (1000 milliliters) and ⅓ (667 milliliters). We used a mountain dew round cylinder bottle in all of our tests because it was the best type of bottle more than the rest of the bottle and we did a lot of research and that bottle was the most common bottle to build a bottle rocket . We filmed videos on both water amount and they both went really high except there was a .2 second difference between the two amounts. Overall the group decided that ⅓ was the highest since it beat ½ by .2 seconds. Some Manipulated variables are The water

But wait! These are all examples of different types of liquids so it makes sense they have different densities. What does this have to do with water? Shouldn’t water all have the same density? (Yes! Maybe?) Well it turns out there are different things that can affect the density of water. For example, think about the different types of water. What type of water is in the ocean? (Salt water!) And what type of water is in our lakes and rivers? (Fresh water!) Yeah! So it turns out that adding salt in different amounts can affect the density of water. Let’s see how salt can affect density.

    One possible source of error that can affect the results was that a mercury thermometer was used instead of an electronic one. The use of a mercury

In the third stage of this experiment, the density of a liquid was determined and compared to known standards. A 100ml beaker was filled to about half-full with room-temperature distilled water. The temperature of the water in ◦C was recorded in order to compare to known standards later. A 50ml beaker was then weighed on a scale in order to determine mass and recorded. A sample of the distilled water with an exact volume of 10ml was then placed in the 50ml beaker using a volumetric pipette. The 50ml beaker with the 10ml of water was then weighed again and the initial mass of the beaker was subtracted from this mass to obtain the mass of the 10ml of water. With the volume and the mass of the water now known, density was calculated using d = m/V and recorded in g/ml. This process was then repeated to check for precision and compared to standard values to check for accuracy. Standard values were obtained from CRC Handbook, 88th Ed.