The two screenshots are my graphs from my data you can put it in the lab report -The excel spreadsheet is my data which was use
The two screenshots are my graphs from my data you can put it in the lab report -The excel spreadsheet is my data which was used in the graphs as well -Please use Harvard referencing and in text citations (at least 3) -There is a copy of the lab report template with the rubric. -There is another Lab report that has been submitted to Turnitin so feel free to read over and understand the lab but make sure you don′t copy it – Maximum word count is 1500 – The aim is to find out the relationship between the concentration of HCL and the rate of the reaction
Sheet1
| Mass (g) at different concentrations mol.dm^-3 | mass (g) loss at diffrent concentrations mol.dm^-3 | |||||||||||
| Concentration of HCL | Concentration of HCL | |||||||||||
| time(s) | 0.400 | 0.800 | 1.200 | 1.600 | 2.000 | time(s) | 0.400 | 0.800 | 1.200 | 1.600 | 2.000 | |
| 0 | 85.954 | 99.526 | 88.577 | 100.030 | 91.764 | 0 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | |
| 30 | 85.938 | 99.482 | 88.480 | 99.902 | 91.567 | 30 | 0.016 | 0.044 | 0.097 | 0.128 | 0.197 | |
| 60 | 85.905 | 99.427 | 88.380 | 99.771 | 91.405 | 60 | 0.049 | 0.099 | 0.197 | 0.259 | 0.359 | |
| 90 | 85.900 | 99.383 | 88.311 | 99.677 | 91.291 | 90 | 0.054 | 0.143 | 0.266 | 0.353 | 0.473 | |
| 120 | 85.900 | 99.345 | 88.263 | 99.602 | 91.208 | 120 | 0.054 | 0.181 | 0.314 | 0.428 | 0.556 | |
| 150 | 85.899 | 99.322 | 88.215 | 99.551 | 91.144 | 150 | 0.055 | 0.204 | 0.362 | 0.479 | 0.620 | |
| 180 | 85.893 | 99.317 | 88.186 | 99.508 | 91.097 | 180 | 0.061 | 0.209 | 0.391 | 0.522 | 0.667 | |
| 210 | 85.893 | 99.305 | 88.179 | 99.489 | 91.065 | 210 | 0.061 | 0.221 | 0.398 | 0.541 | 0.699 | |
| 240 | 85.893 | 99.305 | 88.175 | 99.472 | 91.042 | 240 | 0.061 | 0.221 | 0.402 | 0.558 | 0.722 | |
| 270 | 85.893 | 99.300 | 88.168 | 99.462 | 91.021 | 270 | 0.061 | 0.226 | 0.409 | 0.568 | 0.743 | |
| 300 | 85.893 | 99.300 | 88.163 | 99.458 | 91.006 | 300 | 0.061 | 0.226 | 0.414 | 0.572 | 0.758 | |
| total loss: | 0.061 | 0.226 | 0.414 | 0.572 | 0.758 | |||||||
| Rate | Concentration | |||||||||||
| 0 | 0.000 | |||||||||||
| 0.0008166667 | 0.400 | |||||||||||
| 0.00165 | 0.800 | |||||||||||
| 0.0032833333 | 1.200 | |||||||||||
| 0.0043166667 | 1.600 | |||||||||||
| 0.0059833333 | 2.000 | |||||||||||
,
MUFP Chemistry
Lab Assessment 2
2018-2019
|
Name |
|
|
CEG number |
080 |
|
Signature |
Time allowed: Up to 1 hour and 30 minutes (practical only)
Instructions
1. Listen carefully to instructions from the staff members and you must stop immediately if asked to do so.
2. You must work safely at all the times and wear appropriate clothing.
3. If you need help or any additional equipment raise your hand up.
4. Scientific Calculators are allowed.
5. Before you do your practical your teacher will explain what you are going to do and might carry out a demo– you are advised to listen carefully and take notes.
Information to candidates
1. Before you go to the lab, you must have read the risk assessment attached together with this lab report template.
2. Only use this template to prepare for your lab-report which must be done electronically in Word and submitted on Turnitin by Wednesday, 1 May 2019.
3. You must submit your signed paper copy to your tutor in class on Thursday, 2 May 2019.
4. Graphs or diagrams can be done by hand and then scanned for submission.
5. A coursework submission form must be included with the lab report.
6. If you fail to meet the deadline, your work will be treated as a late submission and the result will be capped at 40%.
Total marks for this paper: 35
Marking Criteria (This is a simplified version of the rubric calculator)
Quantitative Practical Task – 35 Marks
|
Planning (P) |
Total |
13 |
|
|
P1 |
Introduction (include hypothesis) |
1 |
|
|
P2 |
Variables |
3 |
|
|
P3 |
Materials/Apparatus |
1 |
|
|
P4 |
Safety Precautions |
1 |
|
|
P4 |
Apparatus Diagram |
2 |
|
|
P5 |
Method |
5 |
|
|
Obtaining and Processing Evidence (O) |
Total |
12 |
|
|
O1 |
Safety Precautions- protective clothing, disposal of materials, handling of spillages, general safety awareness. |
2 |
|
|
O2 |
Techniques- effective use of a given quantitative procedure |
3 |
|
|
O3 |
Results- show results correctly on the results table |
1 |
|
|
O4 |
Processing Results- Draw a table to show loss in mass (g) at each time interval. Use the data on the table to construct appropriate graph(s) to compare the effect of concentration on the rate of reaction. If appropriate, include a suitable method to deduce the order of reaction with respect to the hydrochloric acid. |
6 |
|
|
Discussion and Evaluation (E) |
Total |
10 |
|
|
E1 |
Simply state results |
1 |
|
|
E2 |
Use of scientific knowledge to explain results |
4 |
|
|
E3 |
Comment on anomalies |
1 |
|
|
E4 |
Comment on the reliability of the method |
1 |
|
|
E5 |
Conclusion(s) |
2 |
|
|
E6 |
Recommendations on further work |
1 |
Quantitative Analysis- Physical Chemistry
Aim: to investigate the effect of increasing the concentration of hydrochloric acid in the reaction between hydrochloric acid and marble chips.
Introduction :
Marble is a metamorphic rock composed of calcium carbonate. Hydrochloric acid reacts with calcium carbonate to form calcium chloride, water and carbon dioxide.
The rate at which carbon dioxide is produced provides a method of measuring the rate of reaction. The most convenient way of doing this is by following the loss in mass as the gas is evolved, because carbon dioxide is sufficiently dense to cause measurable decreases in mass using a standard laboratory balance
Prediction:
Variables:
|
Independent Variable (main controlled variable-input) |
Dependent Variable (responding variable-output) |
|
Other controlled variables: (variables that should be kept constant to achieve a fair experiment/test) |
Materials: (You are advised to make appropriate annotations for clarity before/during the practical and then to rewrite this explicitly. )
|
Hydrochloric acid (2M) |
Marble chips |
|
2 Measuring cylinders |
Conical flasks |
|
Top-pan balance capable of weighing to three decimal places |
Stop watch |
|
Spatulas |
Eye protection |
|
Weighing boats |
Distilled water |
Safety Precautions: (Give at least three lab specific and two general safety precautions appropriate with reasons)
|
SAFETY PRECAUTION |
REASON(S) |
|
1. |
|
|
2. |
|
|
3. |
|
|
4. |
|
|
5. |
Apparatus Diagram(s): (*Draw a well labelled, simple apparatus diagram. You can also use suitable information technology programmes. Any apparatus diagrams taken from the internet should be cited appropriately).
Instructions: (You are advised to make appropriate annotations during the practical and then to rewrite this using the right format and reflecting on how you did the practical for your method. )
1. Weigh out 2.5g of marble chips onto a weighing boat.
2. Using the measuring cylinder, transfer 25cm3 of hydrochloric acid to a conical flask and loosely plug the neck of the flask with cotton wool (Prepare the acid solutions as shown by the table at the top of the next page).
3. Weigh the conical flask containing the acid.
4. Remove the cotton wool-plug and immediately add the marble chips to the acid and start the stopwatch and place back the cotton wool-plug. Gently agitate the conical flask as the reaction takes place.
5. Record the mass every 30s for 5 minutes (10 readings). The starting mass will be the mass of the conical flask + acid + 2.5g of marble chips.
6. Using your processed data, plot appropriate graph(s). Deduce the rates of the reactions at different concentrations and if possible, find the order of reaction with respect to hydrochloric acid.
|
Molar concentration |
V of acid (cm3) |
V of water (cm3) |
|
0.4 |
5 |
20 |
|
0.8 |
10 |
15 |
|
1.2 |
15 |
10 |
|
1.6 |
20 |
5 |
|
2.0 |
25 |
0 |
Results Table:
|
|
Mass (g) at different concentrations (mol.dm-3) |
||||
|
Time(s) |
0.4 |
0.8 |
1.2 |
1.6 |
2.0 |
|
0 |
|
|
|
|
|
|
30 |
|
|
|
|
|
|
60 |
|
|
|
|
|
|
90 |
|
|
|
|
|
|
120 |
|
|
|
|
|
|
150 |
|
|
|
|
|
|
180 |
|
|
|
|
|
|
210
|
|
|
|
|
|
|
240 |
|
|
|
|
|
|
270 |
|
|
|
|
|
|
300 |
|
|
|
|
|
|
Total loss (g)
|
|
|
|
|
|
Processing results:
*For your graph(s) you will need to show loss in mass for each time interval, so you are advised to draw another table before you do your graph(s).
How to work out loss in mass
Loss in mass = mass at 0s – mass at any time
END OF EXAM PAPER
Academic Year: 2018-2019
Programme: Medics Undergraduate Foundation Programme
Module: Module 2
Date: September 2018
© OnCampus 2018
,
Quantitative Analysis- Physical Chemistry
Aim: To investigate the effect of increasing the concentration of hydrochloric acid on the reaction between hydrochloric acid and marble chips.
Introduction :
Before introducing the experiment, we should first fully comprehend what is rate and how to measure it. The rate of the reaction is the speed with which reactants disappear and products form for a particular reaction. Mathematically, the rate of the reaction can be measured through the rate law.
rate=k[A]m[B]n
This expression is the rate law for the general reaction above, where k is the rate constant. Multiplying the units of k by the concentration factors raised to the appropriate powers give the rate in units of concentration/time.
The dependence of the rate of reaction on the reactant concentrations can often be expressed as a direct proportionality, in which the concentrations may be raised to be the zeroth, first, or second power. The exponent is known as the order of the reaction with respect to that substance. In the reaction above, the overall order of reaction is given by the following:
order=m+n (Chemistry LibreTexts, 2019)1
(Chemistry-helper.blogspot.com, 2019)2
In the following reaction, hydrochloric acid reacts with calcium carbonate to form calcium chloride, water, and carbon dioxide. We used marbles as a reactant since they are metamorphic rocks composed of calcium carbonate. This reaction is a neutralization reaction.
The rate of the reaction can be measured through multiple tests, where in this case we will measure the loss in mass as the gas is evolving, since carbon dioxide can cause a significant decrease in mass due to its density.
Prediction:
Variables:
|
Independent Variable |
Dependent Variable |
|
Concentration of hydrochloric acid (mol/dm3) |
Mass of carbon dioxide (grams) |
|
Other controlled variables: Time between each interval (30 seconds) Temperature (oC) Pressure (kPa) The size and number of the marbles (grams) (surface area) |
Materials:
|
Hydrochloric acid (2 mol/dm3) (En.wikipedia.org, 2019)4 |
5 Weighing boats |
|
Marble chips (small balls) |
Top-pan balance capable of weighing to three decimal places |
|
Distilled water |
Stop watch |
|
2 Measuring cylinders (25ml) |
Eye protection |
|
5 Conical flasks (100ml) |
Spatula |
|
Cotton wool |
Safety Precautions:
|
SAFETY PRECAUTION |
REASON(S) |
|
1. Wear lab coat |
To prevent any corrosive material from contacting our clothes and leading to burns |
|
2. Wear safety goggles |
To avoid any irritations from calcium carbonate and calcium chloride |
|
3.Wear nitrile gloves |
To protect hands from corrosive material like hydrochloric acid |
|
4.Handling of spillages |
To avoid any possible contact with the solutions |
|
5.Disposal of materials |
To avoid atmospheric and environmental pollution |
Apparatus Diagram(s):
Instructions:
1. A specific volume of acid was measured with a measuring cylinder and added it to a conical flask. Then a specific volume of water was measured with a different measuring cylinder and added it to the same conical flask. this step was repeated 5 times with different volumes of hydrochloric acid and water making 5 different flasks with different concentrations as shown in the following table.
|
Molar concentration |
V of acid (cm3) |
V of water (cm3) |
Flask Number |
|
0.4 |
5 |
20 |
1 |
|
0.8 |
10 |
15 |
2 |
|
1.2 |
15 |
10 |
3 |
|
1.6 |
20 |
5 |
4 |
|
2.0 |
25 |
0 |
5 |
2. 2.5g of marble chips were weighed in a weighing boat through the top-pan balance.
3. Conical flask 1 was loosely plugged with a cotton wool, and weighed.
4. The weight was neglected after pressing tare.
5. The cotton wool was then removed to add 2.5g of marble chips. The stopwatch started immediately after and the cotton wool was placed back.
6. The mass was recorded every 30 seconds for minutes (10 readings).
7. Steps 2 till 6 were repeated 4 times with the rest of the conical flasks.
Results:
|
Mass (g) at different concentrations (mol.dm-3) |
|||||
|
Time(s) |
0.4 |
0.8 |
1.2 |
1.6 |
2.0 |
|
0 |
2.500 |
2.500 |
2.500 |
2.500 |
2.500 |
|
30 |
2.485 |
2.434 |
2.398 |
2.371 |
2.350 |
|
60 |
2.470 |
2.372 |
2.368 |
2.250 |
2.214 |
|
90 |
2.458 |
2.327 |
2.309 |
2.149 |
2.092 |
|
120 |
2.458 |
2.297 |
2.257 |
2.072 |
1.995 |
|
150 |
2.452 |
2.265 |
2.210 |
2.011 |
1.920 |
|
180 |
2.451 |
2.252 |
2.193 |
1.958 |
1.863 |
|
210 |
2.441 |
2.239 |
2.133 |
1.920 |
1.820 |
|
240 |
2.447 |
2.238 |
2.124 |
1.886 |
1.782 |
|
270 |
2.442 |
2.238 |
2.120 |
1.860 |
1.753 |
|
300 |
2.440 |
2.238 |
2.082 |
1.837 |
1.729 |
|
Total loss (g) |
0.06 |
0.262 |
0.418 |
0.663 |
0.771 |
|
Mass loss(g) at different concentrations (mol/dm3) |
|||||
|
Time Intervals(seconds) |
0.4 |
0.8 |
1.2 |
1.6 |
2.0 |
|
0 |
0 |
0 |
0 |
0 |
0 |
|
30 |
0.030 |
0.066 |
0.102 |
0.129 |
0.15 |
|
60 |
0.035 |
0.128 |
0.132 |
0.25 |
0.286 |
|
90 |
0.042 |
0.173 |
0.191 |
0.351 |
0.408 |
|
120 |
0.042 |
0.203 |
0.243 |
0.428 |
0.505 |
|
150 |
0.048 |
0.235 |
0.29 |
0.489 |
0.58 |
|
180 |
0.049 |
0.248 |
0.307 |
0.542 |
0.637 |
|
210 |
0.059 |
0.261 |
0.367 |
0.58 |
0.68 |
|
240 |
0.053 |
0.262 |
0.376 |
0.614 |
0.718 |
|
270 |
0.058 |
0.262 |
0.38 |
0.64 |
0.747 |
|
300 |
0.06 |
0.262 |
0.418 |
0.663 |
0.771 |
|
Concentration (mol/dm3) |
Initial Rates (x10-3 mol/dm3.s) |
|
0 |
0 |
|
0.4 |
0.5 |
|
0.8 |
2.2 |
|
1.2 |
3.4 |
|
1.6 |
4.3 |
|
2 |
5 |
Discussion:
The first graph shows the mass loss of the marble chips (CaCO3) in different concentrations with respect to time. The graph shows that as the concentration increases from 0.4 till 2 mol/dm^3, the mass loss increased from 0.06 till 0.771 grams. That mass loss of the marble chips is the same mass produced for carbon dioxide.
The second graph is to show how to get the initial rate for one of the concentrations (0.8mol/dm^3).
To do so, we draw a tangent on the curve of the variation of mass loss at the initial
point so that we can calculate the gradient which is the rate. The tangent is shown in the second graph where the rate is 2.2 (mol/dm3.s).
We do the same thing for the rest of the graphs and get the remaining rates. The third graph shows the concentrations and their corresponding rates.
The graph shows a straight line which means they are directly proportional. Hence based on this graph, the order of the reaction is first. We could also see how doubling the concentration, doubles the rate which verifies that the order is first.
The reaction is: 2HCl +CaCO3 => CaCl2 + CO2 + H2O
This reaction is also an exothermic reaction, where the heat is released to the surroundings and that can be detected by a thermometer.
For a chemical reaction to occur, the particles of the reactants have to collide with sufficient energy to react. According to collision theory, if there is more concentration, there will be more particles available to collide hence the chance of successful collisions is much higher. This will lead to faster disappearance of the marble chips and faster production of carbon dioxide.
The results were as predicted since the more concentration of the reactant, the rate will increase due to them being directly proportional.
Evaluation:
It is not safe to say that the experiment is reliable since we only did it once. The experiment has to be done more than once in order to check whether its reliable or not. However, the experiment done is used in most curriculums and is trusted by many educational institutions.
An alternative to checking the rate is measuring the volume of the gas using a gas syringe.
Using a cotton wool could be risky if not put correctly, because that might affect the mass of carbon dioxide by it escaping from the flask. Instead, we could have used a cork which would guarantee that the gas cannot escape, making the results more accurate and the experiment more precise. Even though carbon dioxide is dense, we could have used a gas syringe to check its volume which would have also been accurate. A colorimeter may be used if one of the constituents are coloured.
The size of the marble chips is not constant, and the surface area is a factor that might affect the rate, hence this explains the small fluctuations in the graphs.
Getting the half-life would have been a suitable method to also check the order of the reaction.
Conclusion:
As the concentration of a reactant increases, the rate increases. This means the reactant disappears faster and the product is formed faster. The rate of the reaction can be deduced through measuring the mass of the product and studying its changes. The graph between the concentrations and the rates shows a straight line which shows that the reaction is of first order with respect to hydrochloric acid.
Referencing:
Collepals.com Plagiarism Free Papers
Are you looking for custom essay writing service or even dissertation writing services? Just request for our write my paper service, and we'll match you with the best essay writer in your subject! With an exceptional team of professional academic experts in a wide range of subjects, we can guarantee you an unrivaled quality of custom-written papers.
Get ZERO PLAGIARISM, HUMAN WRITTEN ESSAYS
Why Hire Collepals.com writers to do your paper?
Quality- We are experienced and have access to ample research materials.
We write plagiarism Free Content
Confidential- We never share or sell your personal information to third parties.
Support-Chat with us today! We are always waiting to answer all your questions.
