Exam 7: Atoms and Spectra

An atom that has gained one or more electrons is called an isotope.

The type of elements present in a gas can be determined by studying the ____.

The NASA Curiosity rover exploring Mars carries a number of scientific instruments, including a spectrograph (a device for recording a spectrum), and a high intensity laser. On several occasions, Curiosity has fired its laser at the surface of a rock sample, while observing the process with a spectroscope. The laser is intense enough to vaporize the atoms on the surface of the sample into a hot, excited gas. Why is this a useful technique for the rover to employ?

Absorption lines are produced by ____.

The _______________ is the amount of energy needed to pull an electron completely away from the nucleus.

If absorption lines of sodium are not present in a star's spectrum, the star must not contain any sodium.

A certain type of atom can only absorb certain wavelengths.

What physical situation is necessary to create an absorption spectrum?

An astronomer records the spectrum of light coming from a distant star. Describe what information the astronomer can deduce from this stellar spectrum, and what physical principles she would apply.

The particle in an atom that carries a negative charge is the ____.

A star like the Sun emits a(n) ____ spectrum.

What is the use of the Doppler effect able to tell you about the motion of an object? What is it unable to tell you?

Physicists and astronomers usually refer to the permitted orbits of an atom as the atom's _______________ levels.