Transcript Elements from Stardust

Elements from Stardust
Build a Diagram
Find Hydrogen 1, Hydrogen 2 and Hydrogen 3
Bohr atom models.
Illustrate
Find typical Helium Bohr atom models.
Illustrate
How might Hydrogen atoms combine to form a
helium atom?
Draw a diagram to illustrate your hypothesis.
Why would Hydrogen nuclei with neutrons be
important for this process?
Atomic Nuclei Collide
• Like many other stars, the Sun is made mostly
of one element………Hydrogen.
• This Hydrogen exists at tremendously high
pressures and hot temperatures.
• The temperature in the Sun’s core is about 15
million degrees Celsius.
At the high pressures and hot
temperatures found inside the sun and
other stars, Hydrogen does not exist as
either a solid, liquid or gas.
Instead, it exists in a plasma state.
Plasma state of mater, atoms are
stripped of their electrons and the
nuclei are packed close together.
• Remember that atomic nuclei contain protons,
which means that nuclei are positively
charged. Normally, positively charged nuclei
repel each other.
• But inside stars, where matter is in the plasma
state, nuclei are close enough and moving fast
enough to collide with each other.
• When colliding nuclei have enough energy,
they can join together in a process called
nuclear fusion.
• In nuclear fusion, atomic nuclei combine to
form a larger nucleus, releasing huge amounts
of energy in the process.
• Inside stars, nuclear fusion combines smaller
nuclei into larger nuclei, thus creating heavier
elements.
Elements from the Sun
• A Hydrogen nucleus always contains one
proton. However, different types of Hydrogen
nuclei can contain 2 neutrons, 1 neutron or no
neutrons at all.
• Inside the Sun, Hydrogen nuclei undergo a
nuclear fusion reaction that produces Helium
nuclei.
• It requires a Hydrogen with Neutrons in the
nuclei.
• This for of Hydrogen is rare on Earth, but is more
common inside the sun.
• Two Hydrogen nuclei fuse together, they release a great
deal of energy.
• This reaction is the major source of the energy that the sun
no produces.
• Hydrogen is the fuel that powers the sun.
• The sun will eventually run out of Hydrogen, in an estimated
5 billion years.
• More and more Helium builds up in the core, the sun’s
temperature and volume also changes.
• These changes allow different nuclei fusion reactions to
occur.
• Over time, two or more Helium nuclei combine to form
the nuclei of slightly heavier elements.
• First two Helium nucleus can join wit the berylium
nucleus, forming a carbon nucleus.
• A Helium nucleus can join with a carbon nucleus
forming Oxygen.
• But stars the size of our Sun do not have enough
energy to produce elements heavier than oxygen.
Elements From Large Stars
• As they age, larger stars become even hotter
than the sun.
• These stars are large enough to produce
heavier elements like Magnesium and Silicon.
• In Massive stars, fusion continues until the core
is almost all iron.
• The matter in the sun and planets around it,
including Earth, originally came from a
gigantic supernova that occurred billions of
years ago.
• If this is true, it means that everything around
you was created in a star.
Characteristics of Stars
• Astronomers estimate 300-400 billion
stars exists just in our galaxy alone
with over an approximate 100 million
different galaxies like ours.
• These stars differ in many features,
including size, mass, color, temperature,
and brightness.
Our Star
• Our sun has a diameter of about
1,392,684km, or about 109 times the
diameter of Earth.
• The sun is actually a medium sized star.
• Medium sized stars make up the majority of
the stars you can see in the sky.
• ¾ of the sun is made of Hydrogen with the
rest being mostly Helium.
• The remaining trace elements such as
oxygen, neon, carbon and iron etc.
• The Sun is a G-type main-sequence star (G2V)
based on spectral class and it is informally
designated as a yellow dwarf because its visible
radiation is most intense in the yellow-green portion
of the spectrum, and although it is actually white in
color, from the surface of the Earth it may appear
yellow because of atmospheric scattering of blue
light
• G2 indicates its surface temperature, of
approximately 5778 K
• V indicates generates its energy by nuclear fusion
of hydrogen nuclei into helium.
• Sun fuses about 620 million metric tons of hydrogen
each second.
http://www.kidsastronomy.com/stars.htm
• Using the above labeled website research
each of the following getting basic facts.
• Also sketch what each on would look like.
Red Dwarf Star
Yellow Star
Blue Giant Star
Giant Star
Super Giant Star