Here are the energy levels in a fantasy hypothetical hydrogen-like atom. (you cannot use the rydberg constant, 2.18 x 10-18 j, for this problem, therefore). what is the frequency of a photon that is absorbed when an electron goes from level 2 to level 4? energyn = 4 -2.10 x 10-19 jn = 3 -3.20 x 10-19 jn = 2 - 5.20 x 10-19 jn = 1 - 9.80 x 10-19 j

Smog is the term used to describe the combination of fog and smoke

Which statement is true about hcl? (5 points) select one: a. it is a salt because it increases the concentration of metallic ions. b. it is a salt because it is formed by the reaction of an acid and a base. c. it is an acid because it increases the concentration of hydroxyl ions. d. it is an acid because it increases the concentration of hydronium ions.

Aroller coaster is traveling at 13 mi./s when you purchase a hill that is 400 m long and down the hill exonerate at 4.0 m/s squared what is the final velocity of the posterior found your answer to the nearest number