Question

The minimum amount of unstable atoms needed to produce an uncontrolled chain reaction is called _____.

Answer 1

Critical Mass of the substance. 

Answer 2

The correct answer is:

The minimum amount of unstable atoms needed to produce an uncontrolled chain reaction is called critical mass.

The explanation:

when:

-Critical mass is the minimum amount of something required to start or maintain any project or venture. In nuclear physics, critical mass is the smallest mass of material that will start a chain reaction in a nuclear bomb or reactor. Both kinds of critical mass begin chain reactions.

- The atomic mass is the mass of an isotope of an element in atomic mass units.

-The atomic number or proton number of a chemical element is the number of protons found in the nucleus of an atom. It is identical to the charge number of the nucleus. and In an uncharged atom, the atomic number is also equal to the number of electrons.

So, The correct answer here is critical mass