Nitrogen -13 has a half life of 10 minutes how long will it take for a sample of 500 g to be reduced to 62.5 g?

30 minutes

Explanation:

Use half life equation:

A = A₀ (½)^(t / T)

where A is the final amount, A₀ is the initial amount, t is time, and T is the half life.

A = A₀ (½)^(t / T)

62.5 = 500 (½)^(t / 10)

0.125 = ½^(t / 10)

t / 10 = 3

t = 30

It will take 30 minutes.

what experimental evidence led scientists to change from the previous model to this one?

a few of the positive particles aimed at a gold foil seemed to bounce back.

the colors of light emitted from heated atoms had very specific energies.

experiments with water vapor showed that elements combine in specific proportions.

cathode rays were bent in the same way whenever a magnet was brought near them.