A sample of wood that originally contained 100 grams of Carbon-14 now contains 12.5 grams. How old is this sample?

• 5.7 x 10³

• 11.4 x 10³

• 17.1 x 10³

• 22.8 x 10³

Tags

NGSS.HS-PS1-8

Which of these statements describes what happens during radioactive decay?

• A stable isotope interacts with an unstable isotope

• An unstable isotope bonds with a stable isotope

• An unstable isotope breaks down and becomes stable

• A stable isotope breaks down and becomes unstable

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NGSS.HS-PS1-8

The age of a rock sample can be determined by finding the relative amount of a parent isotope that has changed into a daughter isotope within the sample. Which property of radioactive decay allows the age of the rock to be determined in years?

• releases energy

• releases energy

• happens in all rocks

• happens at a set rate

Tags

NGSS.HS-PS1-8

Each atom has a half-life that is:

• The same for all atoms

• Unique and happens at a set rate

• Different depending on the amount

• Half-life is not a real thing

Tags

NGSS.HS-PS1-8

Gold-191 has a half-life of 12.4 hours. If a lab starts with sample of 10 mg, how much will remain after 37.2 hours?

• 5 mg

• 2.5 mg

• 1.25 mg

• 0.625

What is the half-life of Carbon-14 according to the graph?

• 57 years

• 5700 years

• 23000 years

• 1000000 years

Which type of radioactive decay can be stopped by a piece of paper?

• alpha

• beta

• gamma

• zeta

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NGSS.HS-PS1-8

Which type of radioactive decay can only be stopped by a think layer of lead or concrete?

• alpha

• beta

• gamma

• zeta

Tags

NGSS.HS-PS1-8

Carbon-14 has a half-life of 5,700 years. How much of a 1000 g sample will be left after 11400 years?

• 1000 g

• 500 g

• 250 g

• 125 g

Tags

NGSS.HS-PS1-7

Which two things cause an atom to be unstable and therefore radioactive?

• Having more than 82 protons

• Having too many energy levels

• Not having a proton:neutron ratio of 1:1 for small atoms and 3:2 for large atoms

• Having 8 valence electrons

Tags

NGSS.HS-PS1-8