Based upon Max Planck's theory of black-body radiation, Einstein theorized that the energy in each quantum of light was equal to the frequency multiplied by a constant, later called Planck's constant. A photon above a threshold frequency has the required energy to eject a single electron, creating the observed effect.
Answer:
The correct answer to you your question is Potassium
Explanation:
Potassium is the most reactive
Atomic mass Carbon (C ) = 12.01 a.m.u
12.01 g ---------- 6.02x10²³ atoms
1.50 g ----------- ??
1.50 x ( 6.02x10²³ ) / 12.01 =
7.51x10²² atoms of C
hope this helps!