Lab3

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Investigation 3Student ID E12008926
Evguenia Kelley
Section1
The purpose of the lab is to identify the compound based on a constant composition by performing a serious of tests. The hydrate is solid crystals compound and appears to be dry: since an ionic compound (salt) is crystallized from an aqueous solution (water), by heating the hydrate the water is released from ionic structure; therefore it is possible to measure the weight of the ionic compound and calculate its ratio to the liquid in the hydrate. The goal of the lab is to establish the identity of a given hydrate (“wet salt”) by comparing the results with known hydrate percentages. Hydrates are ionic compounds (salts) that have a definite amount of water as part of their structure. This “water of hydration” is released as vapor when the hydrate is heated. The remaining solid is known as the anhydrous salt. The general reaction for heating a hydrate is:

The Δ sign means that heat is applied. The percent of water in a hydrate can be found experimentally by accurately determining the mass of the hydrate and the mass of the anhydrous salt. The difference in mass is due to the water lost by the hydrate. The percent of water in the original hydrate can then be calculated using a version of the percent composition formula:

Average Value of Salt in Hydrate = (Salt%1+Salt%2)/2
Average Value of Water in Hydrate = (Water%1+Water%2)/2
Section 2
1. Mass Measurements:
The given hydrate was placed in a beaker and weighted by the scale (The scale was zeroed out with the beaker, before the hydrate was placed inside). The result was recorded in a table (0.605g). The procedure was repeated for accurate results. The result was recorded in a table (0.990g) 2. Heating Process:

The Buncen burner was used in the heating procedure. The burner was turned on and the flame came out from the top part. The beaker filled with the weighted hydrate inside, was held over the open flame...
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