Ziyad lab - Chemitry ASUN LAB PDF

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Chemitry ASUN LAB...

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1 Alotaibi

Lab#1 Laboratory Techniques & M Zayad alotaibi 19th October, 2018 At 4:30 PM Performed At Home CHEM1011-D1-25L

Contents

2 Alotaibi Exercise 1: Length, Temperature, and Mass.................................................................................................3 Data Table 1. Length Measurements.......................................................................................................3 Data Table 2. Temperature Measurements.............................................................................................3 Data Table 3. Mass Measurements.........................................................................................................5 Questions.................................................................................................................................................5 Exercise 2: Volume and Density...................................................................................................................6 Data Table 4. Liquid Measurements........................................................................................................6 Data Table 5. Magnet – Measurement Method......................................................................................6 Data Table 6. Displacement Method.......................................................................................................6 Data Table 7. Archimedes’ method..........................................................................................................6 Questions.................................................................................................................................................7 Exercise 3: Concentration, Solution, and Dilution........................................................................................8 Data Table 8. Initial Concentration...........................................................................................................8 Data Table 9. Dilution Series....................................................................................................................8 Data Table 10. Concentration vs. Density................................................................................................8 Questions.................................................................................................................................................9

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Laboratory Techniques and Measurements Hands-On Labs, Inc. Version 42-0165-00-02

Lab Report Assistant This document is not meant to be a substitute for a formal laboratory report. The Lab Report Assistant is simply a summary of the experiment’s questions, diagrams if needed, and data tables that should be addressed in a formal lab report. The intent is to facilitate students’ writing of lab reports by providing this information in an editable file which can be sent to an instructor.

Exercise 1: Length, Temperature, and Mass Data Table 1. Length Measurements. Object

Length (cm)

Length (mm)

Length (m)

CD or DVD

11.5

115

0.115

Key

5.6

56

0.56

Spoon

14.2

142

0.142

Fork

16.7

167

0.167

Data Table 2. Temperature Measurements. Water

Temperature (°C)

Temperature (°F)

Temperature (K)

Hot from tap

40

104

313.15

Boiling

100

212

373.15

Boiling for 5 minutes

101

213.8

374.15

Cold from tap

20

68

293.15

Ice water – 1 minute

5.1

41.18

278.25

Ice water – 5 minutes

7

44.6

280.15

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Data Table 3. Mass Measurements. Object

Estimated Mass (g)

Actual Mass (g)

Actual mass (kg)

Pen or pencil

5

8

0.008

3 Pennies

6.5

7

0.007

1 Quarter

3

5

0.005

2 Quarters, 3 Dimes

20

15.5

0.0155

4 Dimes, 5 Pennies

20

20.5

0.0205

3 Quarters, 1 Dime, 5 Pennies

30

36

0.0036

Key

5

8.2

0.0082

Key, 1 Quarter, 4 Pennies

18.4

20

0.0020

Questions A.

Water boils at 100°C at sea level. If the water in this experiment did not boil at 100°C, what could be the reason? Atmospheric pressure play vital role in that, if the atmospheric pressure is less it will go below to 100.

B.

While heating two different samples of water at sea level, one boils at 102°C and one boils at 99.2oC. Calculate the percent error for each sample from the theoretical 100.0°C. I found -5% error and 9% error

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Exercise 2: Volume and Density Data Table 4. Liquid Measurements. Mass A

Mass B

Mass B - A

Liquid

Volume (mL)

Graduated Cylinder (g)

Graduated Cylinder with liquid (g)

Liquid (g)

Density g/mL

% Error

Water

25

29.3

53.6

23

0.95

4

Isopropyl alcohol

25

29.8

54.2

24.6

0.89

8

Data Table 5. Magnet – Measurement Method. Object:

Mass (g)

Length (cm)

Width (cm)

Height (cm)

Volume (cm3)

Density (g/cm3)

Magnet

4.2

2.5

0.5

0.6

0.5

6.88

Data Table 6. Displacement Method. Object

Mass (g)

Initial volume of graduated cylinder (mL)

Final volume of graduated cylinder (mL)

Object Volume (mL)

Density (g/mL)

Magnet

4.2

6

7

1

4.2

Metal bolt

8

6

7

1

8

Data Table 7. Archimedes’ method. Object

Mass (g)

Mass of Displaced Water (g)

Volume of Displaced Water (mL)

Density (g/mL)

Metal Bolt

8

1

75

0.013

Magnet

4.2

0.8

60

0.013

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Questions A.

An unknown, rectangular substance measures 3.6 cm high, 4.21 cm long, and 1.17 cm wide. If the mass is 21.3 g, what is this substance’s density (in grams per milliliter)? =1.20 g/mol

B.

A sample of gold (Au) has a mass of 26.15 g. Given that the theoretical density is 19.30 g/mL, what is the volume of the gold sample? =1.35 ml3

C.

What would happen if you dropped the object into the beaker while using the Archimedes’ Principle method instead of submerging the object? An immersed object is buoyed up by a force equal to the weight of the fluid it actually displaces. Upward buoyant force exerted on a body immersed in a fluid is equal to the weight of the fluid the body displaces

D.

How did the magnet’s density measurement using the Archimedes’ Principle compare to the density measurement using the calculated volume? Which method might be more accurate? Why? The calculation of density b using Archimedes principle is different from calculating density measurement. For magnet I obtained a density measurement of 5.0 g/mL using Archimedes’ method. By the calculate method i got density of 7.36g/mL.

E.

You are given a small piece of gold colored material and want to determine if it is actually gold. Using the Archimedes Principle you find that the volume is 0.40 cm3 and the mass is 6.0 g. What conclusions can you reach from your simple density analysis? To find the density I divided the volume by the mass which gives me 15g/cm3. This is significantly less than the density of gold , the gold density is 19.3 g/cm3. so the material is not gold.

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Exercise 3: Concentration, Solution, and Dilution Data Table 8. Initial Concentration. Chemical

Mass of Graduated Cylinder

Mass of Sugar (g)

Total Volume (mL)

Concentration (% m/V)

29.5

8

37.5

0.966

Sugar (C12H22O11)

Data Table 9. Dilution Series. Initial Concentration (% m/V)

Volume Transferred (mL)

Final Concentration (% m/V)

0 mL

0.966

Solution

Volume (mL)

Mass (g)

Density (g/mL)

0

25.0 mL

27.6

1.100

1

25.0 mL

25.2

1.003

0.966

2.5 mL

2

25.0 mL

24.5

0.985

0.097

4.5 mL

0.017

3

25.0 mL

24.6

0.981

0.017

3.0 mL

0.002

4

25.0 mL

24.3

0.977

0.002

6.0 mL

0.001

0.097

Data Table 10. Concentration vs. Density. Concentration vs. Density

concentration 1.2 1 0.8 0.6 0.4 0.2 0 0.96

0.98

1

1.02

1.04

1.06

1.08

1.1

1.12

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Questions A.

How would you prepare 10 mL of a 0.25% HCl solution if 1% HCl was available? How much 1% HCl is needed? How much distilled water is used?

V1 =M2* V2 M1* 25M M1 =0. V1 =10mL M2 =1M V1 /M2 =0. 25x10/1=2. 5mL V2 =M1* I nor dert opr epar e10mLof0. 25M HCl sol ut i on,y ouneeddi l ut e2. 5mLof1M HClt o10mLby addi ng( 10mL-2. 5mL=7. 5mL)wat ert oi t .

B.

From the graph of Concentration vs. Density, created in Data Table 10, what was the relationship between the concentration of the sugar solution and the density of the sugar solution? As the graph show direct proportional so that concentration increase density also increases....