Identifying The Identity Of Two Unknown Metals Essay

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

3. Analyze: What do you notice about the density of the Styrofoam pieces? The density remains the same.

because each of the objects displaced the water by 1 mL, their mass over that mL is their density.

Mole of chlorine : 1.0217g - .221g - .3946 g = .4061 g of chlorine

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

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.

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

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.

The difference between an intensive property and an extensive property is that the extensive property of a substance whereas an intensive property does not.

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

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

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.

XIV. Record your observations of the dried, cooled copper metal and weigh the recovered copper.

Using the direct weighing and weighing by difference methods to find weight and mass of chemicals and compounds.

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: