When does radioactive decay occur?

• When the nucleus of an isotope is unstable
• When the nucleus of an isotope is stable
• When the electrons of an isotope are spinning
• When the electrons of an isotope are shared with another isotope

Tags

NGSS.HS-PS1-8

Radiometric dating is possible because the rates of decay of radioactive isotopes _____.

• change over time
• change from place to place
• are constant
• vary widely

Tags

NGSS.HS-PS1-8

The time it takes for 50% of the nuclei in a radioactive sample to decay to its stable isotope is called _____.

• the daughter product
• geologic time
• the half-life
• the half-time

Tags

NGSS.HS-PS1-8

When an unstable radioactive atom decays, it usually turns into:

• a more stable atom
• a less stable atom
• the exact same atom but with less pure energy
• empty space

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NGSS.HS-PS1-8

The original element that undergoes radioactive decay is known as the...

• daughter element
• half-life
• parent element
• carbon-14

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NGSS.HS-PS1-8

The element that is the product of radioactive decay is known as the...

• daughter element

• half-life

• parent element

• carbon-14

Tags

NGSS.HS-PS1-8

Isotopes are atoms of the same element with a differing number of ____.

• neutrons

• protons

• electrons

• prions

Tags

NGSS.HS-PS1-8

What element is usually used to date fossils?

• uranium-235
• carbon-14
• mercury-203
• thorium-234

What is the half life of Carbon-14?

• 5730 yrs

• 1.2 billion years

• 713 million years

• 1.3 billion years

Tags

NGSS.HS-PS1-8

Which characteristic of Carbon-14 dating helps scientist determine the approximate time a species became extinct.

• Carbon-14 is not present in more recent fossils.

• Carbon-14 increases at a constant rate over time

• Carbon-14 decreases at a constant rate over time

• Carbon-14 is not present in fossils