My lab-write up... what were your results?

Lab #2 Flame Test
Teacher Handout
Pages: N/A


Problem

How can elements be identified by using a flame test?

Background Information

A flame test the procedure of placing an element into a flame and observing the reaction, most notably, the flame?s color. This reaction to a flame is a characteristic that allows this element to be identified among other elements. Sodium, for example, gives off a bright orange flame while copper gives off a green flame.
By studying flame tests, scientists are able to learn about the characteristics of an element and find ways to use it for its reaction to a flame. For example, sodium is used in the manufacture of fireworks due to its orange flame. (Creative Chemistry 2000)

Hypothesis

When exposed to a flame, the elements will produce different physical and chemical reactions which will allow them to be identified among each other.

Materials

? Nichrome Wire
? Cork
? Bunsen Burner
? Eight (8) Nitrate Solutions (LiNO3), Ca(NO3)2, (KNO3), (Cu(NO3)2), (Sr(NO3)2), (NaNo3), (Ba(NO3)2)
? Safety Goggles and apron

Procedure

1. Put on safety gear, and then light the burner. Test the nitrate solution that has been provided at the lab station by applying one or two drops to the nichrome wire as demonstrated by the teacher and placing a drop on the outer flame. The lab partner should observe the color and record the results in the data table. All lab partners should verify the observations before proceeding. DO NOT REMOVE ANY CHEMICALS FROM THE LAB STATION!!! Clean any spills immediately.
2. Clean the nichrome wire after every test by placing it into tap water. After doing so, place the wire into the flame and hold it there until the wire glows and no longer colors the burner?s flame.

Data




Compound -Color of Flame
Lithium Nitrate (LiNO3)- Red
Calcium Nitrate (Ca(NO3)2)- Orange
Potassium Nitrate (KNO3)- Pink
Copper Nitrate (Cu(NO3)2)- Green
Strontium Nitrate (Sr(NO3)2)- Red-Orange
Sodium Nitrate (NaNO3) - Orange
Barium Nitrate (Ba(NO3)2)- Pale Yellow


Observations

? Each element produced a unique color. Lithium Nitrate produced a red flame while Calcium Nitrate produced an orange flame. Potassium Nitrate caused the flame to become a pink color and Copper Nitrate produced a green colored flame. Strontium Nitrate caused the flame to become red-orange, Sodium Nitrate produced an orange flame, and Barium Nitrate formed a pale yellow flame.
? Copper, with its green flame, was the most distinct among the elements. Potassium Nitrate and Barium Nitrate also had very interesting colors.
? Also noteworthy is the fact that when an element was exposed to the flame, the flame seemed to increase in size and heat for a few seconds along with its change in color. This is probably due to the burning of the nitrate in each element.

Analysis

? The flame test was a test for the metal, not the nitrate. This was because the nitrate was the constant. This means that it was in each metal and was exposed to the flame each time. However, the metal was the variable, meaning that it was different each time a different element was tested.
? The wire needed to be cleaned before each new element was tested. Otherwise, residue from the previous element could affect the flame.
? The flame test can be used to identify a metal. When the metal is exposed to a flame, it will produce color in the flame distinct to that element. To determine the element which refers to a specific color flame, refer to Table 2-1.
? In a crime lab, it would be possible to determine the element in an unknown substance by applying a flame test. This is to say that the sample of the substance was not contaminated. Knowledge from Table 2-1 along with other information could be used to determine the element. This could be useful in a crime lab. For example, Potassium is lethal in large doses and could be used to poison a person. If a vile of an unknown substance was found, it would be possible test the substance and see if the flame turns pink. If so

 

PS - Physics >> Chemistry

 

uh what is the point of this thread?

 

Why would anyone want to read all that?

Another post brought to you by SecondBest

 

But another quality thread by Onetre!

 

boring!

 

This is, in fact, the definition of tl, dr.

 

But another quality thread by Onetre!

Comedy is not your strong suit.

 

I never said it was.

 

Teacher comments

1) You did not highlight which colour flame you used (yellow or blue), or which point of the flame you inserted the compounds (cone or tip)

2)"also had very interesting colors. "

Unscientific and irrevelant.

3) "This was because the nitrate was the constant."

This statement is incorrect; Lithium Nitrate has one part nitrate, while Calcium Nitrate has two. The nitrate was not constant throughout the experiment.

4) You make no mention of exposure time.

5) "This could be useful in a crime lab. For example, Potassium is lethal in large doses and could be used to poison a person. If a vile of an unknown substance was found, it would be possible test the substance and see if the flame turns pink. If so, then the substance could easily be potassium."

Completely flawed and entirely untrue.


Result - FAILURE

 

*snicker*

 

Everyone give a round of applause to malkieD2. He is the undisputed king of humor.

 

Sorry buddy, but that wasn't humour. You need to work a little harder on your lab reports.

 

I have the only teacher who doesn't assign lab reports.

Groovy

 

If a vile of an unknown substance was found

I'd like to know where you find vials(*) just lying around all over the place.

 

I hate Science classes.

 

Lab Reports can kiss my A$$.

 

It's times like these I'm glad I made out with malkie over PM

 

Well, here are my results.



Lab No. 2 11/9/03

Identification of Elements by a Flame

Publisher : Teacher Hand-Out
Year Published : Unpublished (2003-Distribution)
Page Numbers : Not Applicable

Experiment Performed By: Darth_Malt

Problem: How can elements be identified by using a flame test?

Background information:
?When solutions of metals are heated in a Bunsen burner flame, they give off characteristic colors. For example, sodium makes the flame turn bright orange ? this is the same orange color made by sodium street lamps and many fireworks. One can be an analytical chemist or forensic scientist in this activity, by finding out what color flames different metal?. (Creative Chemistry 2000)

Hypothesis: The flame from the Bunsen burner will turn different colors depending upon which substance has been applied to the uncontaminated inoculating loop. Careful observation and recording of test result in a Data Table will provide a method by which unknown substances could potentially be identified by the color of the flame through comparison.


Materials:

Inoculating Loop Cork Bunsen Burner
Lithium Nitrate Calcium Nitrate Potassium Nitrate
Copper Nitrate Strontium Nitrate Sodium Nitrate
Barium Nitrate Safety goggles Apron



Procedure:

1. Put on apron and safety goggles.
2. Check that the flame test loop is clean. Do this by holding the metal loop in the hottest part of the Bunsen burner flame. If it is clean, there should be no change in the color of the flame when the metal loop is put in the flame.
3. If the metal loop is not clean, dip it into the solution recommended by the instructor, then hold the loop in the Bunsen burner flame. Repeat this cleaning until there is no more change in the color of the flame.
4. Light the burner.
5. Test the nitrate solution that has been provided at the lab station by applying one or two drops to the inoculating loop as demonstrated by the instructor and place the loop in the outer flame.
6. The lab partner not performing the test should observe the color.
7. Record the results in a data table.
8. Both partners should verify the observations before proceeding.
9. Carefully clean up any chemical spills or drips immediately according to safety rules of the lab.
10. Clean the inoculating loop after each test by placing it in tap water.
11. Place clean inoculating loop in flame, holding until the loop glows and no longer colors the burner?s flame.
12. Test each substance in the same manner, recording the data and cleaning the inoculating loop before proceeding.


Data:



Table 2-1
_________________________________________________________________
|___________COMPOUND________|___________COLOR OF FLAME________ |
| Lithium Nitrate (LiNO3) | Red-Orange |
| Calcium Nitrate (Ca(NO3)2) | Orange |
| Potassium Nitrate (KNO3) | Pink-Orange |
| Copper Nitrate (Cu(NO3)2) | Green-Orange |
| Strontium Nitrate (Sr(NO3)2) | Dark Red |
| Sodium Nitrate (NaNO3) | Yellow-Orange |
| Barium Nitrate (Ba(NO3)2) | Pale Yellow |


Observation:

1. Each compound produces a unique color ranging from pale yellow to dark red, allowing the lab partners the opportunity to learn which colors are identified with each substance being tested.
2. Although no unknown substances were tested in the particular experiment, it could be done by using the Data Table. Unknown substances could be identified in a later experiment by comparing the color of the flame to the flame colors listed in the Data Table for the known substances previously tested.
3

 

Very good Darth_Malt

 

Can someone tell me how randomly posting your homework is considered a quality thread idea?

 

Onetre = Worst. Sock. Ever.

 

Can someone tell me how randomly posting your homework is considered a quality thread idea?

It couldn't be considered such.


Now posting answers to upcoming quiz questions...that would hold some merit.


Provided anyone reading the post has that specific quiz to take.

 

Why are people posting their homework? And why is malkie grading it?

 

I know Chemistry:

BeEr + HuMan = BlaDDered + AngRy

Grade my work please