Periodic Trends: Chemistry

What is a wavelength?

A distance between 2 peaks side by side on a wave

What were the units in a wavelength?

Meters (m) and nm

What is frequency (v)?

How many waves go past a point in a given time

What are the units in frequency (v)?

s-1 and Hz

What is the speed of light (c)?

Speed at which a wave travels

What is a short wavelength mean?

It has a high frequency and high energy

What does a long wavelength mean?

A low frequency and low energy

What is the formula for the speed of light?

2.998 × 108 ms-1

What is the unit for energy?

J

What does h stand for?

Planck’s constant: 6.626 × 10-34 Js

What is the number of electrons the electron shell 1 held?

2

What is the number of electrons the electron shell 2 held?

8

What is the number of electrons the electron shell 3 held?

18

What is a valence electron?

Electrons occupying the outmost shell

What is true about electrons found farther from the nucleus?

They contain higher energy

What does wavelength have to do with energy?

As the wavelength goes up the energy goes down, as the wavelength goes down the energy goes up

Where does the energy come from?

Heat

What is emission?

Electrons losing energy, falling back down, energy is released in the form of colors

What is absorption?

When the electron absorbs energy and jumps shells, the jump it makes depends on the energy

What is the “Ground” State?

When an atom’s electrons are in their lowest energy levels. It’s the atom’s normal and stable form, it’s how they typically are

What is the “Excited” State?

When an atom’s electrons absorb energy and move to a higher energy level. It’s not stable, and the electrons eventually fall back to the ground state. The amount of energy that they absorbed is the amount they have to release to go back down

Why do ions emit different colors of light?

They have different wavelengths = different energy levels and the amount of energy released decides the colors. Ex. = more energy is violet and less is red

What are Energy levels?

Big regions of space around the nucleus, they are like the floors and the higher up they are the more energy they have. Ex.= 1,2,3…7

What are Sublevels?

Regions within an energy level, have the same amount of energy. Ex.= s,p,d,f

What is an Orbital?

3D regions where electrons are likely to be found, it’s the how many people each floor can hold. Ex= how many people each floor can hold

How many orbitals are in the s sublevel?

1

How many electrons do sublevel s hold?

2

How many orbitals are in the p sublevel?

3

How many electrons do sublevel p hold?

6

How many orbitals are in the d sublevel?

5

How many electrons do sublevel d hold?

10

How many orbitals are in the f sublevel?

7

How many electrons do sublevel f hold?

14

Where does the s sublevel start at?

1

Where does the p sublevel start at?

2

Where does the d sublevel start at?

3

Where does the f sublevel start at?

4

What is the Aufbau Principle?

You fill up the lowest energy orbitals first

What is the Hund’s rule?

Orbitals of equal energy in a sub-level fill one electron (e-) at a time before pairing up with the same direction as the 1st one

What is the Pauli Exclusion Principle?

No 2 electrons (e-) in the same orbital can have the same spin