essei data logging

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Title Data Logging On Determination The Hydration Enthalpy Of An Electrolyte. Introduction What is Data Logging? Data logging is the process of using computer to collect data through sensors, analyze the data and save the output the results of the collection and analysis. Data logging is also implies the control of how the computer collects and analyzes the data. Data logging is commonly used in scientific experiments and monitoring systems where there is the need to collect information faster than a human can possibly collect the information and in this case the accuracy is essential. Examples of the types of information and a data logging system can collect include temperatures, sound frequencies, vibrations, times, light intensities, electrical currents, pressures and changes in states of matter. Computer data logging has been used in teaching science in number of countries since the 1980s. As summary, a collection of results is known as data while the process of handling data by using modern computer technology referred to as data logging. Elements of Data Logging Data logging system consists of sensor, interface box and computer with appropriate software. A sensor is a device that responds to some physical property of the environment like temperature, pressure, light intensity, voltage, current and many more. Then, the variation of physical properties is converted into signals that is recognized by a device called interface box. The interface box is used to convert the signal of the sensor to a

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Page 1: ESSEI DATA LOGGING

Title

Data Logging On Determination The Hydration Enthalpy Of An Electrolyte.

Introduction

What is Data Logging?

Data logging is the process of using computer to collect data through sensors,

analyze the data and save the output the results of the collection and analysis. Data logging

is also implies the control of how the computer collects and analyzes the data. Data logging

is commonly used in scientific experiments and monitoring systems where there is the need

to collect information faster than a human can possibly collect the information and in this

case the accuracy is essential. Examples of the types of information and a data logging

system can collect include temperatures, sound frequencies, vibrations, times, light

intensities, electrical currents, pressures and changes in states of matter. Computer data

logging has been used in teaching science in number of countries since the 1980s. As

summary, a collection of results is known as data while the process of handling data by

using modern computer technology referred to as data logging.

Elements of Data Logging

Data logging system consists of sensor, interface box and computer with appropriate

software. A sensor is a device that responds to some physical property of the environment

like temperature, pressure, light intensity, voltage, current and many more. Then, the

variation of physical properties is converted into signals that is recognized by a device called

interface box. The interface box is used to convert the signal of the sensor to a digital signal

which is can be read by the computer. The interface will connected to the computer via a

serial port of computer. Then, computer is used to display the data and read the information

from sensor. Specialised computer software is required so that the computer can interpret

and process the signals from the interface box. Examples of data logging software such as

Data Studio, HOBOware and many more. The sensors, interface box, computer and

appropriate computer software called as the data logging system.

Advantages the Use of Data Logging in Science Teaching

From research that have been carried out, data logging can improves graphing

skills of students and help them to form links between what they have learnt in class with

the process of investigating scientific relationships. The interpretations of graphs is

significantly improved as they have applied the skills of real-time reporting where the graph

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is drawn at the same time as the experiment is performed will encourage reflection and

interpretation among students.

Apart from that, computer data logging practical work also will give more benefits

compared to the conventional approach in the presentation of data. By using data logging,

the quality of written homework was greatly improved as the data can be easily

manipulated and presented in the form of clearly drawn graphs. Real-time data logging

presents the graph on the screen “as it happens” and this is especially beneficial to the less

able student.

Data logging also can save times in pattern of student’s activity in preparing

apparatus and materials, measuring and reporting data towards spent more on observation,

manipulation of data and discussion among students of the results obtained when using this

data logging system. The automatic logging of experimental data and graphical

representations allowed for more focused approach to changes in experimental variables

and discussion of results. It was clear that they have better insight into this experimental

work being performed. Besides, students need to take less prolonged readings and through

the software they can spend more time in analysing information. The immediate visual

feedback via the computer enables ‘on the fly’ adjustment to experiments. In addition,

without the aid of computer data logging spent more considerably more time in data

collection.

In general, we can see that students find information technology to be a good

stimulus for learning. The software tools for calculation and analysis will reduce tasks

considered to be tedious and repetitive into creative opportunities for carrying out

investigation in laboratory. This will increased level of interest among students in bringing

science teaching and learning process into twenty-first century.

Data logger also allows students to collect data from whole range of sources at

one particular time. For example, in evaporation experiment they are not just only

measuring the temperature today, but three or fours variables that might be affecting the

outcome of evaporation. Students are able to collect information anywhere and anytime,

which means a whole community potentially becomes part of the learning environment.

Disadvantages the Use of Data Logging in Science Teaching

One of the disadvantages of using data logging is the special features of data logging

graphing software sometimes gives the variaties of difficulties associated in handling the

data logging software, They need to setup the software more wisely and carefully so that it

does not gives not accurate and not precise result when it was displayed on the computer. If

it was happened, they need to modifiy any devices related so that it can be function well.

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Besides, by using data logging, the students will face difficulties if the devices or

equipments are broken or cannot be function well. So, they need times in repairing the

devices so that they can use to run their experiment. The data logging and computerized

devices really need meticulous care as there are really sensitive tools.

Experiment : Determination Of The Hydration Enthalpy Of An Electrolyte

Theory

The dissolution of a solid electrolyte in water is primary determined by two simultaneously

occur in processes : the destruction of the crystal lattice and the hydration of the ions.

The degradation of the crystal lattice is an endothermic process because energy is required

to breakdown the chemical bonds, whereas the hydration of the ions is exothermic.

Depending on the type of lattice, and both the radius and the charge of the ions (charge

density), the resulting enthalpy of the solution can be either or exothermic.

When a salt exists in both hydrated and dehydrated forms, and one assumes that during the

dissolution of the hydrated salt only the degradation of the crystal lattice occurs, the enthalpy

of hydration can be calculated with Hess’s theorem (Figure 1).

¿] (s) [CuSO4 ∙ 5H 2O] (s)

Cu2+ (aq) SO4 2- (aq)

∆ HCuS O4

+H 2O

∆LHCuS O4

+H 2O

∆LHCuS O4 ∙5 H 2O

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∆LH = ∆LH

n (1.1)

∆H HCuSO4= ∆LHCuS O4- ∆LHCuS O4 ∙5 H 2O (1.2)

∆H H Enthalpy of hydration

∆LH Integral enthalpy of solution

The integral enthalpy of solution can be calculated according to equation

∆LH = Qexpn

(1.3)

Qexp = Qcal ∙ ∆T exp∆T cal

(1.4)

Qexp Heat of solution of a salt

Qcal Electrical work for calibration

∆T exp Corrected temperature difference during the dissolution of the salt

∆T cal Corrected temperature difference during the calibration

n Quantity of salt

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I. Engage

(a) (b)

Picture (a) is about the process melting of an ice while picture (b) is about the

process of freezing of an ice. In processes, heat or energy is involved. But, there are some

different either heat absorbed or heat released. Reaction that release heat termed

exothermic while reaction that absorbed heat termed endothermic. Which one of this picture

is exothermic reaction? Which one of this picture endothermic reaction? How the

temperature or heat of the surrounding changes?

In this experiment, anhydrous copper (II) sulphate and copper (II) sulphate were

used. Both compounds are made up of copper and sulphate but one of them contain water

molecule while the other one do not contain water molecule. Most of the people always have

misconception about the molecular formula of copper (II) sulphate and anhydrous copper (II)

sulphate. Most of them think that the molecular formula of anhydrous copper (II) sulphate is

CuSO4.5H2O while the molecular formula of copper (II) sulphate is CuSO4.

Actually, anhydrous copper (II) sulphate is molecule without molecule of water but

copper (II) sulphate is molecule with water. So, the actual molecular formulae of anhydrous

copper (II) sulphate is CuSO4 while the molecular formula of copper (II) sulphate is

CuSO4.5H2O But, is both of them have same type of enthalpy? If both of them have same

type of enthalpy, which one of them has highest enthalpy value? Which one undergoes

exothermic process and which one undergo endothermic process?

Engage is the process to generate idea or to induce any idea about the topic. The

teacher can use the phenomenon happen in our life, video simulation or figures and pictures

to make the students able to think why it happened. In this experiment, we have used the

formation of ice and the melting of ice to relate both of these situations with endothermic and

exothermic reaction so that the students can start to think. In engage stage, the students will

start to explore about the topic, start to think abstractly and start to formulate and develop

the concepts.

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II. Empower

Method

1) First, the experiment set-up is performed.

2) Then, 24.97g (0.1 mol) of copper (II) sulphate and 15.96g (0.1 mol) of anhydrous

copper (II) sulphate, which has been finely pulverized in a mortar are weighed.

3) The calorimeter is filled with 900mL of distilled water. The magnetic stirring bar is put

into the calorimeter and latter is placed onto heating stirrer.

4) After attaching the heating coil and the temperature probe, the magnetic stirrer is

switched on. Please be aware, do not mistakenly switch on the heating unit.

5) When the equilibrium temperature has been reached in the calorimeter

approximately 5 minutes, the first copper salt is added to the water by pouring it

through powder funnel which has been inserted in the opening in the lid. While doing

so, make sure the entire quantity of salt is added to the water without any loss.

6) The registration of the temperature-time curve is begun first.

7) Ten minutes after the salt has completely dissolved, the electrical calibration* is

conducted in order to determine the total heat capacity of the calorimeter.

*10AV is supplied to the work and power meter for the electrical heating. Performed a

reset and then the free ends of the heating coil’s connection cables are plugged into

the output jacks of the work and power meter. The system is heated continuously,

and the supplied quantity of energy is measured. After electrical energy amounting to

approximately 4000Ws has been supplied, the heating is switched off and the exact

quantity of electrical energy is read from the meter.

8) 10 minutes later the temperature recording is also terminated.

9) The corrected temperature differences, ∆T for the calibration and solution experiment

are determined are determined as shown in Figure 2.

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10) This correction is necessary because of the heat exchange with the surroundings.

The vertical straight line ∆T exp which intersects the lines T 1T 2 and T 3T 4 are drawn in

such a manner that the shaded areas are equal size.

11) For the calibration, ∆T cal is determined analogously from the intersection points of

T 3T 4∧T5T6.

12) The same experiment is repeated to determine the enthalpy of solution for both

Copper (II) sulphates. At least two measurements should be performed for each salt

to avoid errors and to be able to calculate the mean value.

Figure 2 : Graphical determination of the correct ∆T values from the temperature time curve.

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Figure 1 : Apparatus set up

Figure 2 :Picture of sensor

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Result

A) Solution of copper (II) sulphate, CuSO4 ∙ 5H 2O

Time, s Temperature, K Notes

30 0.96

H 2O60 0.96

90 0.88

120 0.63

H 2O + CuSO4 ∙ 5H 2O150 0.37

180 0.15

210 0.11

H 2O + CuSO4 ∙ 5H 2O

4057Ws

240 0.09

270 0.09

300 0.06

330 0.02

360 0.02

390 0.01

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50 100 150 200 250 300 350 400 4500

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

0.88

0.630000000000001

0.37

0.150.11

0.09000000000000010.09000000000000010.0600000000000001

0.020.02

0.01

Graph temperature Vs. time of copper (II) sulphate

0.96

Time, s

Tem

pera

ture

, K

Graph 1

Mass of CuSO4 ∙ 5H 2O = 24.976g

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Mole of CuSO4 ∙ 5H 2O = 24.976249.68

= 0.1

∆T exp = 0.0.09 - 0.02

= 0.07

∆T cal = 0.06 – 0.09

= -0.03

Qexp = Qcal ∙ ∆T exp∆T cal

= 4057 ∙ 0.07

−0.03

= 9466J

Integral enthalpy of solution of CuSO4 ∙ 5H 2O

∆LH = Qexpn

= −9466J0.1mo l

= -94.66 kJ mol-1

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B) Solution of anhydrous copper (II) sulphate, CuSO4.

Time, s Temperature, K Notes

30 0.01

H2O60 0.03

90 0.03

120 1.26

H2O + CuSO4

150 1.29

180 1.29

210 1.29

240 1.28

H2O + CuSO4

4066 Ws

270 1.50

300 1.74

330 2.01

360 2.18

390 2.18

420 2.17

450 2.17

480 2.16

510 2.15

540 2.15

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0 100 200 300 400 500 6000

0.5

1

1.5

2

2.5

0.010.03

0.03

1.261.29

1.29

1.291.28

1.5

1.74

2.01

2.18

2.18

2.17

2.172.16

2.15

2.15

Graph temperature against time of anhydrous copper (II) sulphate

Time, s

Tem

pera

ture

. K

Graph 2

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Mass of CuSO4 = 15.963 g

Mole of CuSO4 = 15.963159.63

= 0.1 mole

∆Texp = 1.3 – 0.03

= 1.27

∆Tcal = 2.19 – 1.29

= 0.90

Qexp = Qcal ∙ ∆T exp∆T cal

= 4066 ∙ 1.270.90

= 5738 J

Integral enthalpy of solution of CuSO4

∆ L H = Qexpn

= 5738 J0.1mol

= 57.38 kJ mol-1

∆ H HCuSO4 = ∆ L HCuSO4 - ∆ L HCuSO4.5H20

= 57.38 – (-94.66)

= 152.04kJmol-1

Discussion.

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Hydrates are compounds that incorporate water molecules into their fundamental

solid structure.

All hydrating water is removed, the material is said to be anhydrous

Enthalpy of solution of copper (II) sulphate is exothermic reaction

Enthalpy of anhydrous copper (II) sulphate is endothermic reaction

The 5H2O in the formula of anhydrous copper(II) sulphate is called the water of

crystallisation and forms part of the crystal structure when copper(II) sulphate

solution is evaporated and crystals form. This crystal structure is broken down on

heating and the water is given off. So, the thermal decomposition is endothermic

as heat is absorbed to drive off the water. Meanwhile, the reverse reaction is

called as and exothermic reaction. This is because it needs adding water to white

anhydrous copper(II) sulphate and the mixture heats up as the blue crystals

reform. The reverse reaction is used as a simple chemical test for water where

white anhydrous copper(II) sulphate turns blue.

The enthalpy change is the ‘enthalpy change of hydration’.

Enthalpy change of reaction is endothermic reaction.

The value of enthalpy change of reaction is 152.04kJmol-1.

CuSO4 (s) + 5 H2O (l) → CuSO4 • 5H2O (s)

CuSO4 (s) + H 2O(l) → CuSO4 (aq)

(ashy white) (deep blue)

Empower is something that gaining a power in particular activity by individuals or

groups. It is also the process of giving power to the students or process that foster and

facilitate their taking of power. Besides, empower also a process to achieve goals or some

effort to understand some critical understanding. So, in data logging learning, the teacher

can empower their student by performing an experiment so that they can have more

understanding about what they have learnt theoretically in class. From data logging process,

the method used is by using a sensor and computer rather than using traditional method. So,

the students can see clearly the result. Hence they can make comparison directly between

their results with the theory. If there’s any differences happen, they can make discussion

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regarding the result they got. The students will construct their concept of learning by

understanding the process involve in the experiment. In this topic, students may be surprised

that energy can either be evolved or absorbed in reactions. To make a chemical bond,

another bond must first be broken. It is the sum of the energy changes in making and

breaking bonds that results in the overall energy change. If temperature sensors and data

logging equipment are available, they may be appropriate in this context. This is because a

temperature sensor attached to a computer can be used in place of a thermometer. It can

plot the temperature change on a graph and make a helpful demonstration to the students of

what happens when chemicals react. This data logging set up might be the basis for a

project where students have to find the mix of chemicals that yield the optimal heat loss or

gain.

III. Enhance

Cold packs and putting ice in towel causes a cooling effect on their person’s head and

temporarily relieve the pain and fever. Explain.

There are two types of cold packs which are small inner bag and an outer bag. The

small inner bag can be just water and the outer bag can be ionic salts such as Ammonium

Chloride or Potassium Nitrate. When the pack is squeezed, the small inner bag breaks the

ionic salt dissolves in water. When the cold pack is used, the chemicals inside the pack are

made to react with each other and this reaction is highly endothermic in nature. Endothermic

reactions involve the absorption of heat. The ammonium nitrate mixing with the water

creates cold. The temperature of cold packs can reach back to normal temperature. The

heat energy is taken into the system from the surrounding. The surrounding in this case is

the person’s head.

Another alternative way in reducing headache or fever is by wrapping some ice inside

a small towel and hold it against forehead. This is a traditional way practiced by our parent to

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cool down the temperature and pain. The concept is the same as the cold pack. As the ice

melts to become liquid water, it would take in energy from the surroundings and melting is

considered an endothermic process. The solid ice will become the system and our forehead

becomes the surrounding. The system takes in heat energy from the surrounding and thus

directly remove heat from our forehead and can reduce pain.

Enhance is something to make it better, to add or contribute to. In data logging

learning, enhance is the third phase after empower stage which is to increase student’s

understanding on a given problem or topic by relating it with the example of application. For

example, if we give some situation or application in our environment or daily life application,

the students will be able to relate the reasons of the situation given on what they have learnt.

So that, they can apply their learning concept in daily life application in order to enable them

to understand and remember. So, in this experiment, we should provide an example related

to endothermic or exothermic reaction. The students may have developed their

understanding about these reactions at empower stage but then when at the enhance

process, they just need to add any additional knowledge by relate in with daily life

applications.

Extension

N2 (g) + 3H2 (g) ↔ 2NH3 (g)

What will happen to the production of ammonia gas reaction if we increase the concentration

the temperature of the reactant mixture?

If the temperature of a reaction mixture is increase, the equilibrium will shift to decrease the

temperature. Based on Le Chatelier’s Principle which stated that if a chemical system at

equilibrium experiences a change in concentration, temperature or total pressure, the

equilibrium will shift in order to minimize that changes a new equilibrium is established. So, if

we increase the temperature, the equilibrium will shift to the reactant part which is left. So,

the reaction will undergo endothermic reaction as it use up heat energy. Ammonia will

broken down into hydrogen and nitrogen gas. An increase in temperature will decrease the

yield of ammonia , NH3.

Conclusion

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As a teacher, we should apply the use of data logger in teaching and learning

process in line with the developments of technology. The use of this type of teaching

process can enhance the learning style and gives the positive impact on teaching Science

process especially. Teacher will use the three steps in data logging process like engage,

empower and enhance to make the students get highly understanding about what they have

learnt. Usually during science theory classes, students do not have the opportunity to

verify the appropriateness of the information that the teacher is putting forward. So, the use

of technology which incorporates data logging will significantly ease the situation and able to

develop logical understanding of the abstract concept. At the same time, they can obtain the

information on the truthfulness of the underlying processes. The use of data logging will

bring cognitive acceleration to learning, as the teachers can support their teaching with

undeniable facts, thus students can be able to revisit any misconception they hold on the

spot.

References

A.Gras-Velazquez, A.Joyce and M. Le Boniec. Impact of Data Loggers on Science Teaching and Learning. Retrieved on 27 Dec. 2012 from http://files.eun.org/netbooks/ACER_Fourier_EUN_Science_pilot_report_2012.pdf

Data Logger. Retrieved on 27 Dec. 2012from en.wikipedia.org/wiki/Data_logger

Declan Kennedy (2000). The Use of Data Laogging in Teaching Physics and Chemistry in Second-Level Schools in Ireland. Retrieved on 27 Dec.2012 from http://www.outlab.ie/forums/documents/the_use_of_datalogging_in_teaching_physics_and_chem_in_second_level_schools_report_ie_111.pdf

Engaged Learning. Retrieved on 29 Dec. 2012 from http://www.gcms.k12.il.us/kummerow/engagedlearn.htm

Lorraine Stefani (2008). Engaging our Students in the Learning Process : Points for Consideration. Journal of International Journal for the Scholarship of Teaching and Learning. Vol. 2, No. 1. Retrieved on 28 Dec. 2012 from http://academics.georgiasouthern.edu/ijsotl/v2n1/invited_essays/Stefani/Invited_Essay_Stefani.pdf

Using ICT and Data Logging in Teaching and Learning of Science. Retrieved on 27 Dec. 2012 from http://www.gov.mu/portal/goc/educationsite/file/inside.pdf

Technology-integrated Science Teaching. Retrieved on 28 Dec. 2012 from www.educ.cam.ac.uk/research/projects/istl/ScT2.doc

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