bell ringer 11-4-10 1. which question(s) did you find difficult on the test yesterday? 2. today you...
TRANSCRIPT
Bell Ringer 11-4-10
1. Which question(s) did you find difficult on the test yesterday?
2. Today you will write about one page of Cornell notes, then you will need a separate sheet of paper for an exit slip.
What we’ve learned so far…
Atoms are made of protons, neutrons and electrons
Protons determine the identity of the element Neutrons determine the isotope Protons and neutrons are located in the nucleus
of the atom
…but what about those electrons?
Electrons in the Atom
November 4, 2010
Rutherford’s model of the atom:Discovered: Atom is mostly
empty space Atom has a small,
positively charged center (nucleus)
Problems: How are electrons
arranged? Why don’t electrons
crash into the nucleus?
How Does a Satellite Stay in Orbit?
Bohr Model Electrons are arranged into
specific orbitals around the nucleus
Electrons have different amounts of energy depending on the orbital they are in
Further away from nucleus = more energy
Closer to nucleus = less energy
Check for Understanding:In your notes: rank the following electrons
from lowest energy to higher energy
1
2
4
3
Energy increases as you move AWAY from the nucleus
4 3 1 2
Electrons can move! Atoms can absorb
energy or emit energy Absorb energy
electrons move to higher orbitals
Release energy electrons move to lower orbitals
Light Energy absorbed/released by atoms can
be in the form of light
Colors of light: ROY G. BIV Red = lower energy Violet = higher energy
Energy Travels in Waves
How are atoms different? Atoms of different elements have orbitals of different
energies. This means they can give off different colors of light!
Atomic emission spectrum: the unique pattern of light emitted by a specific atom
Check for UnderstandingThe atomic emission spectrum of an atom is given
below. Identify which element it is in your notes using the known spectra below.
Hydrogen
Krypton Helium
Xenon
Which element am I???
How do scientists know what stars are made of? Stars are far away and extremely hot, so we
can’t take direct samples of gas! Scientists look at the light given off by the star
hydrogen helium
neon
Spectrum of light from the Sun
Exit SlipFor credit today, copy and complete the following questions
on a separate sheet of paper using your notes:
1. Electrons are arranged in ____________ around the nucleus.
2. How does the energy of orbitals change as you move away from the nucleus?
3. Atoms _____________ energy when electrons move to higher orbitals.
4. Atoms _______________ energy when electrons move to lower orbitals
5. Purple light is __________________ in energy than red light.
6. What is an atomic emission spectrum?