Transcript Chapter 3: Elements and the Periodic Table

Chapter 3: Elements
and the Periodic Table
Section 5: Elements from
Stardust
Conditions in Stars
• The sun, and many other stars, is made mostly of
hydrogen.
• Extremely high pressure and temperatures (15
million degrees Celsius)
Plasma
• The state of matter that consists of a gas-like
mixture of free electrons and atoms stripped of
electrons.
• Highest energy
• Exists in stars, comet tails, high-voltage electricity,
and fluorescent lights.
Checkpoint 1
• What is plasma?
Checkpoint 1
• What is plasma?
• The state of matter that consists of a gas-like mixture
of free electrons and atoms stripped of electrons.
Elements Form in Stars:
Nuclear Fusion
• Process in which two atomic nuclei combine to form
a larger nucleus, releasing huge amounts of energy.
• Usually nuclei would repel each other (both
positively charged), but are forced together in the
high pressure environment of stars.
• Creates heavier elements than it started with.
o Different isotopes of hydrogen fuse, producing nuclei of
helium, producing huge amounts of energy
Fusion in the Sun
• Hydrogen is the fuel that powers the sun
o Scientists estimate that the sun has enough hydrogen to last
another 5 billion years
• As more helium builds up in the core, the sun’s
temperature and volume change.
• New fusion reactions occur
o Two helium = beryllium
o Helium + beryllium = carbon
o Helium + carbon = oxygen
• Stars the size of the sun don’t contain enough energy to
produce elements heavier than oxygen
• Eventually, shrinks and its elements blow away
o Forms a nebula – cloudlike region of gases.
Elements From Large
Stars
• Larger stars become hotter than the sun and have
enough energy to produce heavier elements, like
magnesium and silicon
• In more massive stars, fusion continues until the core
is almost all iron
• In the final hours of the most massive stars, a
supernova (huge explosion that breaks apart a
massive star, producing temperatures up to 1 billion
degrees Celsius) occurs
o Creates the heaviest elements
Everything is Stardust
• Most astronomers agree that the matter in our solar
system originally came from a gigantic supernova
that occurred billions of years ago.
Checkpoint 2
• What element does the fusion of a helium nucleus
and a beryllium nucleus produce?
Checkpoint 2
• What element does the fusion of a helium nucleus
and a beryllium nucleus produce?
• Carbon
Post-lesson Quiz
1. Which state of matter has the highest energy of
all?
a. solid
b. liquid
c. gas
d. plasma
Post-lesson Quiz
2. What do scientists call a huge explosion that breaks
apart a massive star, producing temperatures up to 1
billion degrees Celsius?
a. nebula
b. supernova
c. plasma
d. fusion
Post-lesson Quiz
3. What is it called when two nuclei are force
together, creating a heavier element and producing
large amounts of energy?
a. nebula
b. supernova
c. plasma
d. fusion
Post-lesson Quiz
4. What do scientists call a cloud-like region of gases
that can form at the end of a medium-sized star’s life?
a. nebula
b. supernova
c. plasma
d. fusion
Post-lesson Quiz
5. Which of the following is not a place that you can
find plasma?
a. comet tails
b. stars
c. flashlights
d. high-voltage electricity