Answer:
Green, Blue, Indigo, Violet
Explanation:
According to Einstein's equation of photoelectric effect, the kinetic energy of emitted photoelectron is the difference between the energy of the incident photon and the work function of the metal. The work function of the metal referee to the minimum energy that must be supplied in order to eject an electron from a metal surface. The energy of the incident photon must exceed the work function of the metal.
When we look at the electromagnetic spectrum, only the selected colours have frequency above the threshold frequency as shown by the image attached below.
Sodium metal forms at the cathode
THE DEFINITION OF PHYSICAL CHANGE: Physical changes are changes affecting the form of a chemical substance, but not its chemical composition. Physical changes are used to separate mixtures into their component compounds, but can not usually be used to separate compounds into chemical elements or simpler compounds. so the answer is that the form of the sugar is changing in water but if you boiled the water till its all evaporated all that will be left is the sugar