An element's atomic number is 40. how many electrons would an atom of this element have? an atom of element a has 111 protons. what would the element's atomic number be? how many neutrons does an element have if its atomic number is 55 and its mass number is 161?

Hello my friend,
since atomic no. = no. of electrons
there will be 40 electrons in that atom.
if and element has 111 protons, atomic no. will be 111.
no. of neutron = 161 - 55 = 106 neutrons.

Most smaller stars don't have a radiative zone.

Answerthis solution will not form a precipitateexplanationsolubility equilbrium:         pbf₂(s)  ⇄ pb²⁺(aq) + 2 f⁻(aq)the solubility product expression is    (we exclude solids from the equilibrium expression).now suppose we have the trial ion product q, which we can define as    then, we can interpret  q as the product of the concentration of the ions that we have and ksp as the product of the ion concentrations that are needed to form a saturated solution.if q > ksp, then that implies that there will be a surplus of ions that exceed the amount that is required to form a saturated solution. a precipitate will then form (the precipitate continually  forms until the surplus ions are removed and q is decreased to ksp's value).if q = ksp, the saturated solution that forms is barely saturated and the precipitate will be minimal.if q < ksp, then the ion concentration will not be enough to form a saturated solution (so no precipitate).using our information, we calculate the trial ion product:     since q = 2.7  × 10⁻⁸ < ksp =  4  ×  10⁻⁸, a precipitate will not form.