Cyclohexane Lab Report

(.1063 KIO31) (1 mol KIO214 g) x 6 mol S2O41 mol KIO= .00298.04150= .259 M

10. The accepted value for the density of aluminum is 2.699 g/cm3. Using this density and the masses of your two samples of aluminum foil, calculate the volume of aluminum in each sample: the regular vs. the heavy duty. (Note: You will have to use a bit of algebra and the formula D = m/v for this calculation!)  You must show all your work. (15 pts)

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

The freezing point constant (Kf) of water is 1.86 °C m-1. Each mass amount and Van’t Hoff factor was calculated then analyzed in a table.

Then we took 8.35mL of salt water and put it in the evaporating dish which we placed over a Bunsen burner until all the water was dried out. The mass of the evaporating dish with the solid was 83.39g which means the mass of the sodium chloride was 0.622g. Next we took the mass and divided it by the volume of the solution which was 8.35mL and got 0.074 as the original concentration. To the get molarity of the salt solution we had to divide the concentration by the mass of the sodium chloride and then multiply by 1000mL to get 1.3M of salt solution. Final thing we had to do was determine the number ions present in 8.35mL so we took 1.3 moles of NaCl and divided it by 1000mL then multiplied by 8.5mL to get 0.01105 number of Na ions and Cl. The data was as I expected for part A because I followed step by step instructions on how to convert from grams to moles and moles to number of molecules and for part B my answer of 1.3 molarity of salt solution matched with key provided on LoudCloud.

2. The least precise measurement was the temperature but more specifically the freezing points of the solutions and solutes. Due to the freezing point only having two significant figures, the data is limited to two significant figures as well.

3. The volume of a fixed mass of a liquid sample increases as the temperature rises from 20 to

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.

Part 1: MULTIPLE CHOICE (48 points). Choose the one alternative that best completes the statement or answers the question. Record your answer on the scantron. Each question is worth 3 points. 1) A student weighed 30.00 µg of sulfur in the lab. This is the same mass as A) 3.000 × 10 4 ng. B) 3.000 × 10 -5 mg. C) 3.000 × 10 -8 g. D) 3.000 × 10 -5 kg. 2) 1)

B. While heating two different samples of water at sea level, one boils at 102°C and one boils at

It is suspected that the freezing point is 64.1oC. Due to the short temperature plateau, It is difficult to determine if the freezing point occurs at during the interval (6:00-6:10). However, it appears to be have been the most reasonable determination for freezing point in comparison to the rest of the plot.

Introduction Molar mass is a fundamental quantity of chemistry. There are multiple ways to find the molar mass of a substance experimentally; one way is to use Freezing Point Depression by using the following equation: ΔT= kf*m (Robinson, 2018). The purpose of this lab was to do just that; measure the freezing point depression of a solution when a solute is added to a solvent, and from that, determine the molar mass of an unknown substance, along with learning about the influence that solutes have on liquid properties. A concept of importance to this experiment is freezing point. According to LibreTexts, “Freezing point depression is a colligative property observed in solutions that results from the introduction of solute molecules to a solvent…and

2-naphthol has a molecular weight of 144.17 g/mol, with a density of 1.22 g/cm3. The melting point of 2-naphthol is in the range of 121 to 123 °C. The stock solution of 2-naphthol has a concentration of 1.9844E-3 M.

After that, it is crucial to convert the mass to volume. The water density at a temperature will aid this process. The compliance of the Volume Occupied by 1.000g of Water Weigh in Air table is deemed necessary throughout the comparison.

3. Calculate the total heat released in each reaction, assuming that the specific heat of the solution is the same as for pure water (4.18J/gK). Use q=mcΔT. Show work here and record your answer in Data Table 2.