H18
November 4th, 2013
Period 5
Purpose:
To demostrate and classify the characteristics.
Objective:
Describe the difference between a physical and the chemical change.
Data Table:
Analysis Questions:
1.) What indicators (at least 3) determine that a chemical change (or reaction) has occurred?
- A change in color, odor, or state of matter.
- A change in color, odor, or state of matter.
2.) What is emitted when a chemical change takes place in the flame test?
- The chemical change that took place was its change of color. Each time that an element was added, the color of the flame would change into a different color.
- The chemical change that took place was its change of color. Each time that an element was added, the color of the flame would change into a different color.
3.) What group, from the periodic table, do these elements exist?
-Barium, Calcium, and Strontium are apart of Alkaline Earth metals; Lithium, Potassium, and sodium are apart of Alkali metals; Chlorine is apart of Halogens.
4.) Do any two elements give the same spectrum of color? Explain why?
-Calcium and Sodium gave off different shades of orange. This is because depending on the amount of energy is given off the element that is turning back to its original form, the particles with resembling transititons creates the color shown.
*http://www.webexhibits.org/causesofcolor/3BA.html
-Calcium and Sodium gave off different shades of orange. This is because depending on the amount of energy is given off the element that is turning back to its original form, the particles with resembling transititons creates the color shown.
*http://www.webexhibits.org/causesofcolor/3BA.html
5.) Recall what a catalyst is in a chemical reaction. What was the catalyst in these reactions?
- A catalyst is what makes the chemical reaction happen. The chemical reaction in these reactions was the gas that was being squeezed into the flame. by squeezing, it made the flame change color.
- A catalyst is what makes the chemical reaction happen. The chemical reaction in these reactions was the gas that was being squeezed into the flame. by squeezing, it made the flame change color.
Critical Thinking:
One way that scientists in a CSI Unit may be able to gather information the crime is through the use of a flame test. In Forensic Chemistry, Toxicology is the study of substances, such as liquid poisons and drugs. It is possible that Toxicologists use a flame test to determine what elements may be in the substances found at the crime scene. Here is an example of a flame test used in Toxicology. Lets say that a mysterious substance was found beside the murder victim. Toxicologists would preform multiple tests, such as a flame test or the use of serology (the study of body fluids). With the use of a flame test, they would be able to determine compounds within the substance, as well as the elements that the compounds are made up of.SOURCE:http://www.chemistryexplained.com/Fe-Ge/Forensic-Chemistry.html
http://www.youtube.com/watch?v=ZcRfitm6caw
My Visual Observations:
Something that is obvious with Ms. Janik's flame test and other recorded flame tests is that for some elements, such as Potassium, that they appear in different colors. In Ms. Janik's flame test, the flame mixed with Potassium appear in my eyes to be light blue while in other tests the flame is lilac/light blue. This may be due to the appearance of the color in the human eye. Our eyes sometimes interpret colors we see differently from what the color actually is. This may explain why some elements in the flame test appear as similar colors but have some of another color within the flame.
* Copper and Selenium was not used during the flame test in class, therefore they are not included in data chart.
