Continuous Spectra

Question 1

What is the spectrum of white light?

Answer 1

Continuous

Question 2

What is each line in a line spectrum caused by?

Answer 2

Each line in a line spectrum is due to light of a certain color and therefore a certain wavelength.

Question 3

What are some features of the wavelength of lines of a line spectrum?

Answer 3

• They are a characteristic of the atoms of that element.

Question 4

How can you identify the element that produced the light?

Answer 4

• The wavelength of lines of a line spectrum of an element are characteristic of the atoms of that element.
• By measuring the wavelengths of a line spectrum, you can identify the element the element that produced the light.
• No other element produces the same pattern of light wavelengths.
• This is because the energy levels of each type of atom are unique to that atom, so photons that are emitted a characteristic of the atom.

Question 5

When do you get a line absorption spectrum?

Answer 5

When light with a continuous spectrum of energy passes through a cool gas.

Question 6

What happens at low temperatures?

Answer 6

Most of the electrons in the gas atoms will be in their ground states.

Question 7

what happens to the photons?

Answer 7

• Electrons can only absorb photons with energies equal to the difference between two energy levels
• Photons of the corresponding wavelengths are absorbed by the electrons to excite them to higher energy levels.=

Question 8

Why are the wavelengths missing from the continuous spectrum when it passes through the cool gas?

Answer 8

• Most of the electrons in the gas atoms will be in their ground states.
• Electrons can only absorb photons with energies equal to the difference between two energy levels
• Photons of the corresponding wavelengths are absorbed by the electrons to excite them to higher energy levels.=

Question 9

What do the black lines represent in the excited gas?

Answer 9

• A continuous spectrum appears with black lines in it corresponding to the absorbed wavelengths.
• Comparisons of absorption and emission spectra of a particular gas, shows that the black lines in the absorption spectrum match up to the bright lines in the emission spectrum.