PHYSICAL SCIENCE REVIEW 3rd Quarter

The formation of elements is known as

• nucleotides

• synthogenesis

• nuclear fission

• nucleosynthesis

The first two elements formed in Big Bang Nucleosynthesis where

• H and Li

• H and He

• H and O

• He and Li

A combination of quarks form a neutron

• 1 up quark, 2 down quarks

• 2 up quarks, 1 down quark

• 3 up quarks, 1 down quark

• 1 up quark, 3 down quarks

This nucleosynthesis happens in the center of stars and is where the elements helium through iron (Fe) are formed.

• Big Bang

• Stellar

• Supernova

• Superdupernova

What element can be formed when three atoms of helium are fused?

• Carbon

• Hydrogen

• Oxygen

• Silicon

A reaction in which two or more nuclei combine to form heavier nuclei.

• combustion

• nuclear fusion

• nuclear fission

• nuclear synthesis

When does a star become unstable?

• Star becomes unstable when it runs out of fuel.

• Star becomes unstable when it contracts and expands.

• Star becomes unstable when its core is converted to Iron.

• Star becomes unstable when the gravity from the center pulls the outer shell of star.

In this process, there’s a buildup of a VERY heavy isotope, then as beta- decays occur, you march up in atomic number and produce heavy product.

• S Process

• R Process

• Nuclear fission

• Proton-proton reaction

One of the reason why heavier elements were not formed during Big Bang nucleosynthesis is...

• No free protons and neutrons

• Gravitational force is too weak

• Universe cooled too quickly

• Process of fusion did not discovered yet

The key ratio found in the universe that confirms the Big Bang

• 25% hydrogen and 75% helium

• 75% hydrogen and 75% helium

• 75% hydrogen and 25% lithium

• 75% hydrogen and 25% helium