Carbon-14 Decay and Calculations

Why do living trees and dried wood have different carbon-14 decay rates?

• Living trees absorb carbon dioxide, maintaining a constant carbon-14 level.

• Dried wood absorbs more carbon dioxide than living trees.

• Dried wood has a higher carbon-14 decay rate than living trees.

• Living trees have less carbon-14 than dried wood.

What happens to carbon-14 during beta decay?

• It converts into carbon-12.

• It emits a beta particle and becomes nitrogen-14.

• It absorbs a neutron and becomes carbon-15.

• It remains unchanged.

Why is the decay rate of carbon-14 in the atmosphere considered constant?

• Because it is only produced in the upper atmosphere.

• Because it is never consumed.

• Because it is only consumed in the lower atmosphere.

• Because it is continuously produced and consumed at equal rates.

How is the rate constant 'k' calculated for carbon-14?

• By dividing the natural log of 2 by the decay rate.

• By dividing the natural log of 2 by the half-life.

• By multiplying the decay rate by the half-life.

• By adding the decay rate to the half-life.

What is the initial decay rate of the old piece of wood when it was living?

• 13.6 counts per minute per gram

• 6.8 counts per minute per gram

• 1.7 counts per minute per gram

• 3.4 counts per minute per gram

How long has the piece of wood been dead if its current decay rate is 3.4 counts per minute per gram?

• 5,730 years

• 22,920 years

• 11,457 years

• 18,000 years

If a tree was alive for 4,000 years, what is its total age including the time it has been dead?

• 18,000 years

• 4,000 years

• 11,457 years

• 15,457 years

How many years does it take for the carbon-14 decay rate to halve?

• 22,920 years

• 18,000 years

• 5,730 years

• 11,460 years

What is the estimated decay rate for wood that is 18,000 years old?

• 3.4 counts per minute per gram

• 0.85 counts per minute per gram

• 1.54 counts per minute per gram

• 1.7 counts per minute per gram

Which formula is used to calculate the final decay rate of carbon-14?

• Final amount = Initial amount - e^(-kt)

• Final amount = Initial amount + e^(kt)

• Final amount = Initial amount * e^(-kt)

• Final amount = Initial amount / e^(kt)