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*Trial 1 Trial 2 Trial 3**g*) 19.437 20.687 18.431

*g*)

*g*)

**Report Sheet.**) See

**Data Analysis C, D**for determining the standard deviation and relative standard deviation for a set of data. Express all of the calculated data with the correct number of significant figures (see

**Data Analysis A**).

**Calculations**

*Trial 1 Trial 2 Trial 3**g*)

*g*)

*g*)

*%*)

_{2}O in hydrated

*Data Analysis,B**%H*)

_{2}O. Advertisement .

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The Gravimetric Analysis is a tests performed in laboratories and techniques that are designed to determine the quantity of an analytical substance (substance that is quantified) in a particular sample. This is done by determining the composition by mass of the specimen using specific instruments and methods.

You can find hydrated salt mass as:Mass of fired crucible, lid and hydrated salt – Mass of fired crucible & lidBelow is the calculated mass of hydrated salt used in all trials

Trial 1—— 21.626g – 19.437g =2.189 gTrial 2—— 25.111g – 20.687g =4.424 gTrial 3——- 22.167g – 18.431g =3.736 g_________________________________________________________________________________________

The mass of anhydrous salt can be calculated as

Mass of fired crucible, lid and anhydrous salt – Mass of fired crucible & lidBelow is the calculated mass of anhydrous salt used in all trials

Trial 1———– 21.441g – 19.437g =2.004 gTrial 2———- 24.702g – 20.687g =4.015 gTrial 3——— 21.762g – 18.431g =3.331 g_________________________________________________________________________________________________

Calculation of the water loss in mass

Mass of hydrated compound – Mass of anhydrous compoundBelow is the calculation of the water loss for each trial

Trial 1——- 2.189g – 2.004g= 0.185 gTrial 2 ——-4.424g – 4.015g= 0.409 gTrial 3 ——-3.736g – 3.3331g =0.405 g________________________________________________________________________________________________Calculated as: Percentage by mass of volatile water within hydrated compound

Mass of water lost / Mass of hydrated compound × 100Below is the percentage of volatile water in all trials.

Trial 1———- 0.185g / 2.189g × 100 =8.45%Trial 2——– 0.404 g / 4.24 g × 100 = $1strongTag26$Trial 3———- 0.404g / 3.7336 g × 100 =10.84 %___________________________________________________________________________________________________

Average H2O % = (8.45 + 9.26 +10.84) / 3 = 9,52 %

Average percent H2O in hydrated salt is 9.52%__________________________________________________________________________________________________The standard deviation is calculated as follows

Let’s make a table and find the (x-average x ) values

^{2}^{2}= 1.1449^{2}= 0.0676^{2}= 0.5184Total ( x – average x)

^{2}= 1.1449 + 0.0676 + 0.5184 = 1.7309n = Number of Trials, = 3

We get the following results by substituting the above values into the S.D formula

S.D . = √( 1.7309 / 3-1)

S.D = √( 0.8655)

S.D = 0.9303

Standard deviation of % of H2O is 0.9303__________________________________________________________________________________________________The relative standard deviation is calculated using the following formula

% RSD = Standard deviation/Mean (average of % H2O)×100

% RSD = 0.93303 / 9.52 × 100

% RSD = 9.772 %Trial 226.111 g- 19.437.g = 2.189 gTrial 322.167.g- 20.687.g = 4.2424 gTrial 322.167.g- 18.431.g = 3.3736 g