Question 1 (1 point) Atomic emission spectra result when... Question 1 options:
ID: 848664 • Letter: Q
Question
Question 1 (1 point)
Atomic emission spectra result when...
Question 1 options:
...an electron changes its spin state.
...an electron moves from a higher (excited) energy level to a lower energy level.
...an electron moves from a lower energy level to a higher (excited) state energy level.
...a metal loses an electron to form a cation.
Question 2 (1 point)
Why do we have to use a spectrophotometer for this experiment, instead of just using our eyes?
Question 2 options:
The human eye is sensitive to the total amount of light present.
The human eye cannot detect ultraviolet or infrared emissions, which may be part of the atomic spectra.
The human eye is more sensitive to some wavelengths than others.
All of the above statements are correct.
Question 3 (1 point)
Which of the following ions is likely to be present as an impurity in many of the samples?
Question 3 options:
A) H+, due to contamination by HCl.
B) Cl-, due to contamination by HCl.
C) Na+, due to contact with the watch glass.
D) Pt2+, due to contamination from the platinum wire.
Question 4 (1 point)
After setting up your individual MeasureNet station, you will acquire an emission spectrum using the MeasureNet spectrophotemeter. What is the correct sequence of steps to follow in order to obtain a spectrum using the MeasureNet spectrophotometer?
Question 4 options:
A) Obtain a background spectrum by pressing the "ZERO" key on the spectrophotometer while there is nothing in the flame.
B) Heat the platinum wire in the flame, then immerse it in distilled water on a watch glass at the base of the burner.
C) Heat the platinum wire in the flame, then immerse it in the sample to be tested on a watch glass at the base of the burner. Have your partner press "SAMPLE" when the solution sizzles.
D) Dip the platinum wire into the beaker of concentrated HCl solution.
A)...an electron changes its spin state.
B)...an electron moves from a higher (excited) energy level to a lower energy level.
C)...an electron moves from a lower energy level to a higher (excited) state energy level.
D)...a metal loses an electron to form a cation.
Explanation / Answer
1. b. an electron moves from a higher (excited) energy level to a lower energy level.
2. . C) All of the above statements are correct.
3. A) H+, due to contamination by HCl.
4. C) Heat the platinum wire in the flame, then immerse it in the sample to be tested on a watch glass at the base of the burn