Introduction
It is necessary to identify the identity of two unknown metals. This is important because a metal scrap yard must know the identities of the metals before they can be recycled. It is also necessary to know what each metal is if a building is to be made using one or more of these metals. Identifying the metals will be done using intensive properties. Intensive properties do not depend on the amount of material present. Density is an intensive property found with the formula D=m/v. Which is defined as mass divided by volume to find the density.
Procedure
First, each metal’s description and weight was recorded. Additionally, the weights of each cylinder used was recorded. Next, a graduated cylinder was filled with 20mL of water and unknown metal II was fully submerged in the water 3 times. Each time, the volumes were recorded and the difference between the final volume and initial volume was calculated. This test was repeated for unknown metal IV.
Calculations
Unknown I and V Masses
Unknown I was weighed 3 times in a graduated cylinder with 20 mL of water in it. Weight 1 came out at 215.672g, weight 2 came out at 216.135g, and weight 3 came out at 216.362g. Averaging the weights gave 216.056g.
Unknown V’s weights came out at 74.065g, 74.623g, and 74.538g. Averaging the 3 weights yielded 74.589g.
Unknown I and V Volumes
Unknown I’s 3 volume measurements came out to be 26.26 mL, 26.25mL, and 26.02mL. Averaging these volumes yields 26.15mL.
Unknown V’s 3volume
(.1063 KIO31) (1 mol KIO214 g) x 6 mol S2O41 mol KIO= .00298.04150= .259 M
This amount was then weighed to be 0.060 g, 21.74% (see figure 2) of the total mass of Panacetin. According to the label, the sucrose should make up about 10% of the composition, thus this sample weighed about 11.74% percent more than expected. This increase of weight may of been caused by many different experimental errors, such as the failure to isolate the solid completely after centrifugation. When extracting the pellet from the bottom of the tube, it is possible that some of the dissolved liquid was collected to, yielding a larger mass.
Mole of chlorine : 1.0217g - .221g - .3946 g = .4061 g of chlorine
because each of the objects displaced the water by 1 mL, their mass over that mL is their density.
3. Analyze: What do you notice about the density of the Styrofoam pieces? The density remains the same.
If I fill up two different containers with different amounts of water, then I will be able to understand the density of the two different mass/volumes of two different containers.
Purpose: Weighing objects. Figuring out the density with an object by calculated volume and Archimedes’ Principle.
D. A sample of gold (Au) has a mass of 26.15 g. Given that the theoretical density is 19.30 g/mL,
XIV. Record your observations of the dried, cooled copper metal and weigh the recovered copper.
The volume of a small test tube and a thin-stemmed pipet were determined in this section of the lab. Water was poured into a small test tube until the water reached the very top edge of the test tube. The test tube was then emptied into a plastic 25 mL graduated cylinder and volume was measured and recorded into data table 3. A think-stemmed pipet was completely filled with water. Drops were carefully counted and emptied into the empty plastic 25 mL graduated cylinder until the water level reached 1 mL. The number of drops in 1 mL was recorded into data table 3. The thin-stemmed pipet had a total volume of 4 mL and that was also recorded into data table 3.
Using the direct weighing and weighing by difference methods to find weight and mass of chemicals and compounds.
In Measuring and Understanding Density, several experiments were performed to find density of regularly shaped objects, irregularly shaped objects, liquids and gasses. An additional experiment was done to find the specific gravity of a sampling of liquids. The purpose of the experiment was to provide a better understanding of density and to be able to extrapolate unknowns based upon these calculations. The experiments yielded data in keeping with Kinetic-molecular theory in regards to the density of water versus its temperature. Key measurements and formulae were also used to determine densities of metal and plastic objects as well as irregularly shaped rocks. It is possible to find the density of an object (be it liquid, gas or
This experiment was performed to observe differences in density based on the chemical makeup of an object. Pennies minted before 1982, pennies minted after 1982, and an unknown metal sample was tested to see if there were any differences in their densities. Ten pennies from each category and the metal sample were weighed using a scale to find mass and the displacement method was used to find their volumes. The masses and volumes were then used to calculate the densities of the pennies (D=m/v). The density of the pre-1982 pennies were 8.6 g/mL while the post-1982 pennies were 6.9 g/mL. The metal sample’s density was 1.7 g/mL. Following the experiment we were given the real densities of each item to calculate the percent error with the formula
An unknown material can be determined by using simple chemical tests and separations which is called as inorganic qualitative analysis. The separation of cations depends on the difference in their propensity to form precipitates. Separation scheme is used to classify cation into five groups on the basis of their physical and chemical behavior opposed to some reagents. Classification is based on whether there is formation of precipitates or not when metal cations react with the reagent. The five groups of cations and the characteristics of these groups are as follows:
In this experiment, The purpose of this experiment is to investigate the measurement of the actual volume contents of volumetric glassware. In the beginning of the experiment, the volumetric glassware should be clean and dry before used. The volumetric glassware, measuring cylinder and pipette should be handled with care and all the precautions were be taken during the experiment was held. This was to ensure to avoid any errors such as parallax error especially while reading water meniscus. This experiment must be repeated three times or more and take the average reading to get more