You are a paleontology professor working at a dig site looking for fossils. You come across a deposit that is emitting radiation. Upon further testing you find that the sample is changing from carbon (atomic number 6) into nitrogen (atomic number 7) as radiation is emitted. What type of radiation is it?

β particles

Explanation:

The most common radioactive isotope of carbon is C-13.

The unbalanced nuclear equation is

Let's write the question mark as a nuclear symbol.

The main point to remember in balancing nuclear equations is that the sums of the superscripts and the subscripts must be the same on each side of the equation.  

Then

13 =  A + 13, so A =  13 - 13 = 0, and

6 = Z + 7, so Z  = 6 - 7 = -1

Then, your nuclear equation becomes

The particle with "zero" mass and a charge of -1 is an electron, so the balanced nuclear equation is

The radiation consists of β particles (electrons)