Question

If the half-life of C-14 is 5730 years, how much C-14 would be left from a 5000 year-old sample that started as 150 grams?
N = No(1/2)t/T​

Answer 1

Answer:

81.9 grams

Explanation:

From the question we are given;

• Half-life of C-14 is 5730 years
• Original mass of C-14 (N₀) = 150 grams
• Time taken, t = 5000 years

We are required to determine the mass left after 5000 years

• Using the formula;

• N = No(1/2)^t/T​, where N is the remaining mass, N₀ is the original mass, t is the time taken and T is the half-life.

   t/T = 5000 yrs ÷ 5730 yrs

    = 0.873

N = 150 g ÷ 0.5^0.873

   = 150 g × 0.546

   = 81.9 g

Therefore, the mass of C-14 left after 5000 yrs is 81.9 g