La vida media radiactiva

The video tutorial explains how radioactive decay makes substances stable by changing their nuclei and emitting radiation. It uses molybdenum-99 as an example, which decays into technetium and then into stable ruthenium-99. The concept of half-life is introduced, explaining how it helps determine when a radioactive substance becomes safe. The half-life of molybdenum-99 is about 3 days, and understanding this helps in safely storing radioactive waste until it poses no health risk.

What is the process called when an unstable isotope emits radiation to become stable?

• Nuclear fusion

• Radioactive decay

• Isotope stabilization

• Chemical reaction

Which element is formed when molybdenum-99 decays?

• Technetium

• Ruthenium

• Uranium

• Plutonium

How can scientists determine when a radioactive substance is no longer dangerous?

• By observing its color change

• By testing its chemical properties

• By calculating its half-life

• By measuring its temperature

What is the half-life of molybdenum-99?

• 3 days

• 1 day

• 1 year

• 6 months

Why is knowing the half-life of a substance important?

• To calculate its density

• To determine its melting point

• To safely store radioactive waste

• To predict its color change