If an atom has a mass number of 23, which of the following is always true? the number of protons in the nucleus does not equal the number of neutrons. the atomic number is less than 11. the atom is not an isotope. the atom has an odd number of neutrons.

Why do scientists believe that light is made of streams of particles? scientists believe that light is made of streams of particles because only the presence of photons can explain phenomena observed during experiments on the photoelectric effect. these observations include only some frequencies of light causing the ejection of electrons, no time gap existing between light striking a metal and electrons being ejected, and intensity having no effect on the kinetic energy of the ejected electrons.

Dalton’s model of an atom is the best described as a) a solar system b) a solid sphere c) a cloud d) a scoop of chocolate chip ice cream

What are two different ways you could find the value of a? explain these methods.