Separation Of A Mixture Do-Own-Lab Report

Separation of a Mixture Do-Your-Own-Lab

What you will need to do: 1. Create a flow chart for the separation of your unknown mixture – BERFORE doing lab 2. Create data table – BEFORE doing lab 3. Do lab 4. Analyze data – calculate percent composition of your unknown mixture = 15 points = 30% 5. Write a complete lab report = 35 points = 70%

1. A flow chart is often used to illustrate the steps involved in the separation of a mixture. Flow charts are constructed BEFORE attempting to separate the mixture. Think of it as roadmap you intend to follow to get to the final products. The flow chart is included in the Methods section of the lab report.
EXAMPLE OF A FLOWCHART for Separation of a Mixture
of Unknown Composition

a) Products of EACH STEP are ‘boxed’ b) Methods are written to the sides of the ‘connector lines’ c) FINAL PRODUCTS should be in the last boxes
You will be separating a dry mixture of SAND, SALT, and IRON FILINGS
2. Data Tables are also constructed BEFORE attempting a lab. They should include places to record all data you expect to collect. Thought should be given to: * number of trials to be performed * measurements to be made and methods for collecting the measurements * collection of both starting and ending measurements for comparisons * calculations and analysis which will need to be performed using the measurement data * graphs and charts which will be made using the measurement and/ or calculated data

EXAMPLES OF A DATA TABLES for Various Types of Experiments

3. You are to carry out the lab you have designed to separate your sand/ salt/ iron mixture. You must be able to complete the separation in 1 lab period. Final weighing will occur the next day after the separated constituents have had time to dry.

4. You must analyze the data. For the Separation of a Mixture lab, you must determine the percent composition for your unknown sample. Normally, a graph or chart is included in the Analysis and Results section. You will need to design and complete some sort of graph or chart to display the results of you analysis.

5. You will need to write a lab report. Each person must write his/her OWN lab report. While it is expected that some portions of the lab report will resemble that of your lab partner, the Discussion section must be unique to each individual. Lab reports whose Discussion sections are too similar will be penalized points for copying.

DUE DATES:
Flow Chart and Data Tables: ____________________ Date of Lab: ____________________ Lab Report: ____________________
Possible Materials To Be Use: Unknown Mixture of Sand/ Salt / Iron Filings chemical apron beakers (size?)
Bunsen burner and tubing chemical scoop electronic balance evaporating dish filter paper funnel gloves (disposable) goggles graduated cylinder (size?) magnet plastic bag (why?) pipets (disposable?) ring stand and ring sparker stirring rod test tubes wash bottle watch glass water weigh boats wire mesh w/ ceramic center

Safety Precautions:
The materials in this lab activity are considered relatively nonhazardous. Observe all normal laboratory safety procedures. Wear chemical splash goggles whenever chemicals, glassware, or heat ore used in a chemistry laboratory. Since the Bunsen burner will be used for this lab goggles MUST be worn at all times. In addition, those with long hair must securely tie back their hair. Long-sleeved or loose clothing must be secured away from flames.

What must be contained in the Lab Report:

1. Title * descriptive 2. Introduction/ Objectives Section * what principles will be demonstrated by this lab * why is this a good method to demonstrate these principles * how will the principles be demonstrated by this lab 3. Materials list * include amounts and sizes 4. Safety precautions 5.
Methods Section - with flowchart * step-by-step * numbered 6. Results Section * data tables * graphs, charts 7. Discussion Section

Name: Terry Testtube | Due Date: 8/27/1999 | Lab Partners: Excellent helper #1 | Excellent helper #2 | |

SAMPLE LAB REPORT
Effect of Gravity on Rate of Fall
Introduction:
During this laboratory exercise we attempted to show that the force of gravity has the same effect on all falling bodies near the earth. We intended to show this by dropping several objects in normal atmospheric conditions, and in a vacuum chamber. Our tests showed that while everyday experience may indicate that not all objects fall toward the earth at the same rate, they are submitted to the same force of gravity. Materials:

Feather
Coin
Stopwatch
Meter stick
Vacuum chamber
Vacuum pump
Magnet

The vacuum chamber must have some special mechanism so that the fall of any object placed inside of it can be controlled and measured. Our vacuum chamber had an internal trapdoor that could be opened by waving a magnet nearby. Methods: 1. Drop a feather and a coin in the open air, three times from a height of 2.5m 2. Time their decent using a stopwatch – record this time in Data Table
1. 3. Drop a feather and a coin in a vacuum chamber – BEFORE evacuating the gases from the chamber, three times from a height of 2.5m 4. Time their decent using a stopwatch – record this time in Data Table 1 5. Drop a feather and a coin in a vacuum chamber – AFTER evacuating the gases from the chamber, three times from a height of 2.5m. 6. Time their decent using a stopwatch – record this time in Data Table 1
Results:
Collected data:
All drop heights inside and outside of the vacuum chamber were 2.5m

Data Table 1: | Open-air drop(s) | In chamber (gas-filled)(s) | In chamber (evacuated)(s) | Feather (1.23g) | Trial 1 | Trial 2 | Trial 3 | Trial 1 | Trial 2 | Trial 3 | Trial 1 | Trial 2 | Trial 3 | | 2.36 | 2.42 | 2.29 | 2.34 | 2.29 | 2.34 | 1.48 | 1.48 | 1.47 | Coin (2.78g) | 1.47 | 1.50 | 1.48 | 1.49 | 1.48 | 1.50 | 1.47 | 1.48 | 1.48 |
Results Continued:
Calculations:
The average time for each type of drop conducted was found by averaging the measurements of the three trials. These averages will be used for all following calculations, and example is given below.
Example: 2.36s+2.42s+2.29s= 7.07s 7.07s/3 = 2.36s
The averages found through these calculations are given in the following table.

Calculation Table 1: | Open-air drop | In chamber (gas-filled) | In chamber (evacuated) | Feather (1.23g) | 2.36s | 2.32s | 1.48s | Coin (2.78g) | 1.48s | 1.49s | 1.48s |

Figure [ 1 ]

Time (s)

These averages were then used to find the observed acceleration by using a derivative of the basic motion equations: a=2∆x/ (∆t2) Since the change in position was known to be 2.5m, and the average time was found from the experiment, the acceleration was easy to calculate for all scenarios.
Example: a=2∆x/(∆t2) a=(2(2.5m))/((2.36s)2)=0.89m/s2

These calculations have been completed for all drops and are given in the table below.

Calculation Table 2: | Open-air drop | In chamber (gas-filled) | In chamber (evacuated) | Feather (1.23g) | 0.89m/s2 | 0.88m/s2 | 9.8m/s2 | Coin (2.78g) | 9.8m/s2 | 9.8m/s2 | 9.8m/s2 |

Discussion:
The findings of the experiment seem to be quite conclusive and clearly let us meet our objective. We intended to show that gravity applies an equal force on all falling bodies. To do this, we evaluated the trials to find the observed acceleration of the dropped items. When you look at the acceleration for the falling coin it is nearly the same in all three situations, and very close to the accepted quantity for acceleration due to
gravity.
When you look at the acceleration of the falling feather you can clearly see a different pattern. The feather falling in the vacuum had nearly the same acceleration as the coin. However, when the feather fell in either scenario where the air was not removed, it fell at nearly one-tenth of vacuum chamber rate. With such a clear pattern, the slowed acceleration could easily be attributed to the force of air resistance. This friction-like force would oppose the force applied by gravity and slow the feather’s decent. Air resistance would have a
Discussion Continued: significantly higher effect on the feather than the coin since the feather has so much less mass in comparison to its cross-sectional area. There is some implicit error in this procedure because it was nearly impossible for our lab group to stop any ambient breezes in the lab room. That said, our group had considered this in advance and therefore we measured the drop time in the non-evacuated chamber as well as in the open-air room for two control scenarios for comparison. Looking at all of the data and calculation results it is clear that all falling bodies have the same effect of gravity applied to them. That said, this may not all ways seem true at first glance because the falling body’s behavior is still the sum of all forces acting on the body.

Name: _____________________________ Due: __________ Partners: _________________________
A lab report must accurately present all of the activities of a lab, whether the objectives were met, any data calculation, and errors. Further requirements are below. | Good | Fair | Poor | Title &Introduction | Title * Present/Descriptive/succinctSuccinct statement of: * Objective * Hypothesis justified with background | Title * Problems with description or succinctnessStatement of: * Objective * Hypothesis not justified with background | Title * Nondescriptive or absent or not at all succinctStatement of: (1 of 2 min) * Objective * Hypothesis not justified with background | Methods | Materials | * All materials listed | * All critical materialslisted, only a few items left out | * Missing any critical materials | | Procedure | * Logical summary ofprocedures, with enough detail to be repeated by someone not in course * Highlight variables (in- /dependent) | * Logical summary ofprocedures with enough detail to be repeated (with little extrapolation) * Highlight variables (in- /dependent) | * Summary ofprocedures with barely enough detail to be repeated * Highlight variables (in- /dependent) | Results | Data | * Unaltered collecteddata is presented in clearly organized manner, and is annotated so that it is clear where all values come from in procedure | * Collected data is presented in clearly organized manner, and is annotated to show where all values come from in the procedure | * Data is presentedwith a minimal explanation as to where it came from | | Calculations | * All calculations areexplained and shown,with each different type of calculation having its own example for clarification. Results are tabulated and presented graphically if necessary. | * Critical calculationsare explained and shown, with each different type of calculation having its * own example forclarification. All calculated results are presented in tables. | Critical calculations are explained and shown, with calculated results presented in tables. * No example forClarification or the calculation is incorrect | Discussion | Discussion | Clear, logical and accurate discussion of: (ALL BULLETS) * Completion of objectives * Restate hypothesis and support/refute with data * Summarizing graphs or tables * Inherent errors * Future improvements * SCIENCE ACCURACY * STATEMENTS SUPPORTED BY DATA | Clear, logical and accurate discussion of: (3 of 5) * Completion of objectives * Restate hypothesis and support/refute with data * Summarizing graphs or tables * Inherent errors * Future improvements * SCIENCE ACCURACY * SOME STATEMENTS SUPPORTED BY DATA | Clear, logical and accurate discussion of: (2 or less) * Completion of objectives * Restate hypothesis and support/refute with data * Summarizing graphs or tables * Inherent errors * Future improvements * SCIENCE ACCURACY * STATEMENTS NOTSUPPORTED BY DATA |
Lab Report Total Score: ___________________________