Question

If we start with 1.000g of cobalt-60, 0.675g will remain after 3.00 years. this means that the half life of cobalt-60 is ______ yr.

Answer 1

The half-life of cobalt-60 is 5.27 years.

Step-by-step explanation:

The half-life of cobalt-60 can be determined using the given data:

1. After one half-life, 50% of cobalt-60 remains.
2. After two half-lives, 25% remains.
3. After three half-lives, 12.5% remains.

Since 0.675g of cobalt-60 remains after 3.00 years, we can see that 50% of the original 1.000g has decayed.

Therefore, 0.500g of cobalt-60 remains after one half-life, which is 5.27 years.

The half-life of cobalt-60 is 5.27 years.