Flame Tests and Element Colors in Chemistry

The video tutorial, set in Hall B of the Harvard Science Center, demonstrates flame tests using a propane torch and metal ions in chloride salt solutions. The instructor shows how to observe the characteristic colors emitted by different metal ions, such as calcium, sodium, and barium, when placed in a flame. A diffraction grating is used to analyze these colors more precisely. The tutorial covers the setup, execution, and analysis of flame tests, highlighting the unique color emissions of various metal ions.

What is the purpose of using a propane torch in the experiment?

• To heat the metal ions to their excited state

• To cool down the metal ions

• To create a vacuum environment

• To measure the temperature of the flame

How are metal ions introduced into the flame?

• Using a wooden stick

• By pouring directly from a beaker

• Using a plastic spoon

• With a piece of platinum wire at the end of a glass rod

What color does calcium emit when placed in the flame?

• Bright orange

• Bright red

• Bright green

• Bright blue

What is the role of diffraction grating in the experiment?

• To increase the flame temperature

• To diffract the colors of the flame for better analysis

• To change the color of the flame

• To extinguish the flame

Which metal ion is noted for its fast color change in the flame?

• Barium

• Sodium

• Lithium

• Strontium

Which of the following metal ions is not mentioned in the flame test?

• Neon

• Iron

• Potassium

• Copper

What is the characteristic color of sodium in the flame test?

• Bright purple

• Bright green

• Bright yellow

• Bright pink