Please help me with these questions its only a few! (100 Points) 1) An atom has an average atomic mass of about 72.5 amu.

What is the chemical symbol for the atom?

Consult the periodic table.

Pb

Eu

Ge

U

2) Atom A emits mainly X-rays when excited. Atom B emits primarily ultraviolet radiation when excited.

What can be said about the transition between energy levels for Atom B?

Consult the electromagnetic spectrum.

There is no correlation between the distance between energy levels and the energy emitted.

The change between energy levels for atom B is less than for atom A.

There is no difference between the distances electrons in atom A and atom B must travel.

The change between energy levels for atom B is greater than for atom A.

3) What is the photoelectric effect?

The photoelectric effect changes with the emission of an atomic spectrum.

The photoelectric effect is the number of electrons in the shells around a nucleus.

The photoelectric effect is due to the release of electrons from an atom.

4) What information can the atomic emission spectra of a distant star yield for scientists?

age of the star

orbit of the star

elements found within the star

composition of nearby planets

5) Phosphorus has an atomic number of 15.

What is the electron configuration for an electronically neutral atom of phosphorus?

Use an aufbau diagram and fill it in if you need to.

1s22s22p63s23p6

1s22s22p63s23p3

1s22s22p63s23p5

1s22s22p63s23p4