Question

For this investigative phenomenon, you will need to determine the composition of the new star using a spectrometer. This will help scientists determine the star's approximate age. You will complete Part I and Part II trials of the experiment. Record your observations and test measurements in the lab report below. You will submit your completed report.

Procedure:
Part 1: Clean the platinum wire by dipping it in the hydrochloric acid (HCI) and heat the wire in the hottest part of the flame. Dip the wire in the test tube containing a solution with a known element. Then stick the wire into the hottest part of the flame and record the color of the flame.
Part 2: Use the spectroscope to observe the color of the flame for each of the given elements. Record the colors and wavelength values of the elements’ emission line. Use the spectroscope to observe the light emitted from a star. Record the color and wavelength values of the brightest lines in the spectrum.
What are the controlled, independent, and dependent variables?

Answer 1

Controlled variables: The distance between the spectrometer and the flame, the intensity of the flame, the type of flame (oxidizing or reducing), and the concentration of the solution in Part 1.

Independent variables: The type of element being tested in Part 1 and the type of star being observed in Part 2.

Dependent variables: The color and intensity of the flame in Part 1, and the colors and wavelength values of the emission lines in both Parts 1 and 2.

Step-by-step explanation:

Controlled variables refer to factors that are kept constant during an experiment to ensure that any changes observed are due to the independent variable. In this investigation, several factors are kept constant to ensure accurate results. The distance between the spectrometer and the flame is controlled to ensure that all observations are made at a consistent distance.

The intensity of the flame is also controlled to ensure that all flames being tested have similar intensities. The type of flame (oxidizing or reducing) is controlled to ensure that all observations are made under similar conditions. Finally, in Part 1, the concentration of the solution being tested is controlled to ensure that all solutions have similar concentrations.

Independent variables refer to factors that are intentionally varied during an experiment to observe their effects on the dependent variable. In this investigation, two independent variables are being tested: the type of element being tested in Part 1 and the type of star being observed in Part 2.

By testing different elements in Part 1, scientists can determine how different elements emit light under similar conditions. By observing different stars in Part 2, scientists can determine how different stars emit light under similar conditions.

Dependent variables refer to factors that are expected to change as a result of changes in the independent variable. In this investigation, several dependent variables are being observed: the color and intensity of the flame in Part 1, and the colors and wavelength values of the emission lines in both Parts 1 and 2.

By observing these dependent variables, scientists can determine how different elements emit light under similar conditions, as well as how different stars emit light under similar conditions. This information can then be used to determine the composition of new stars using a spectrometer, which can help scientists determine their approximate age.