Radioactive Decay and Half-Lives

The video tutorial explains radioactive decay, focusing on the decay of parent isotopes into stable daughter products. It introduces the concept of half-life, detailing how it measures the time required for half of a radioactive substance to decay. The tutorial provides examples and calculations for isotopes like carbon-14 and potassium-40, demonstrating how to solve problems using half-life data.

What is the primary purpose of the radioactive decay data chart?

• To help solve radioactive decay problems

• To provide information on stable elements

• To list all known isotopes

• To calculate atomic mass

Which of the following is NOT a parent isotope mentioned in the chart?

• Carbon-14

• Potassium-40

• Uranium-238

• Helium-4

What does the term 'half-life' refer to in radioactive decay?

• The time it takes for a parent isotope to completely decay

• The time it takes for half the mass of a parent isotope to transform into a daughter product

• The time it takes for a daughter product to become stable

• The time it takes for an isotope to become radioactive

Why is Carbon-14 used for dating recent events?

• It is abundant in nature

• It is a stable isotope

• It has a very long half-life

• It has a relatively short half-life

Which isotope has a half-life closest to the age of the Earth?

• Carbon-14

• Uranium-238

• Potassium-40

• Rubidium-87

In the sample problem, how many half-lives did it take for 200g of Carbon-14 to reduce to 50g?

• Two half-lives

• One half-life

• Three half-lives

• Four half-lives

How many years ago was a sample part of a living tree if it originally contained 200g of Carbon-14 and now contains only 50g?

• 5,700 years

• 17,100 years

• 22,800 years

• 11,400 years

What is the half-life of Potassium-40?

• 5,700 years

• 1.3 billion years

• 4.5 billion years

• 49 billion years

If a sample of Potassium-40 is 3.9 billion years old, how many half-lives have passed?

• Two half-lives

• Four half-lives

• One half-life

• Three half-lives

After three half-lives, how much Argon-40 is present if the original mass of Potassium-40 was 300g?

• 37.5g

• 75g

• 150g

• 262.5g