Chem 215 Exam #1

What creates the differences in brightness of stars?

Size of the star, distance from the eye, molecular makeup, temperature (higher=brighter)

How do we get information about stars without going to them?

We can use the radiation emitted

What do the black lines in a spectroscopy show?

That there is something in the way that is absorbing wavelengths of colors we cannot see.

True or False: The same color of a planet and star means that it has the same process of light

False

Explain what a blackbody is

Dark, dense, opaque object that emits light

True or False: Red waves on a spectroscopy means longer wavelength and less energy while purple waves are shorter wavelength and higher energy

True

What does the unit Angstrom measure?

Bond distance

What is the crest of a wave and what is the trough of a wave?

The crest is the tip of the wave and the trough is bottom part

What is the height of the wave called?

Amplitude

What is the difference between destructive waves and constructive waves?

Destructive waves create dark spots while constructive waves makes things brighter

What are Isotopes

atoms of the same element with different numbers of neutrons

What are Allotropes

Different forms of an element

Who discovered that the proton and neutron are in the middle? (dont think we need to know this)

Rutherford

Higher energy = ________ orbit/radius = ________ stability

Higher energy = larger orbit/radius = low stability

What is the difference between orbit and orbital?

Orbit: concentric circles describing electron motion characterized by n

Orbital: three-dimensional region in space it is probable to find an electron

What does n represent as a quantum number? What does it need to be?

n - the principal quantum number → positive integer

What does l represent as a quantum number? What does it need to be?

l - the angular momentum quantum number - an integer from 0 to `n-1

What does ml represent as a quantum number? What does it need to be?

ml - the magnetic moment quantum number - an integer from -l to +l

What does ms represent as a quantum number? What does it need to be?

ms - spin quantum number - +½ or -½

What are nodes

white spot from nucleus where there is 0% chance to find electrons

What is the formula for nodes?

n - 1

What is coulombic attraction? What is the force of attraction based on?

attraction between a positive and negative particle. Force of attraction is based on distance (longer the distance, the weaker the attraction) and charge (the larger the distance between the charges, the stronger the attraction)

What is ionization energy? How does it change as you move across the periodic table?

energy needed to completely remove an electron from neutral atom

Increase left to right because # of protons increases

Increases bottom to top because the atomic radius decreases

The higher the charge is the strong the attraction is so the electrons are pulled in closer, decreasing atomic size.

What is electron affinity? What is the formula for it? How does it change along the periodic table?

adding an electron

X(y) + -e = X- (y)

The more negative it is the easier it is to add an electron

As you move to the top and the right, the easier it to add an electron

What kind of bond holds metals with nonmetals? (+ electron movement)

Ionic bonding w/ electron transfer

What kind of bond holds nonmetals with nonmetals? (+ electron movement)

Covalent bonding w/ electron sharing

What kind of bond holds metals with metals? (+ electron movement)

Metallic bonding w/ electron pooling

Which electrons typically are used for interactions with other atoms?

Valence electrons.