What is the frequency of light that has an energy of 3.98 x 10-18 J

For ai it's atomic number is 13 and it's mass number is 27 how many neutrons does it have

Which is an example of the practical pursuit of alchemy? a. forming perfect substances. b. transforming base metals. c. developing metalworking techniques. d. linking spiritual characteristics with material substances.

In a ni-cd battery, a fully charged cell is composed of nickelic hydroxide. nickel is an element that has multiple oxidation states. assume the following proportions of the states: nickel charge proportions found 0 0.17 +2 0.3 +3 0.33 +4 0.5 (a) determine the mean of the nickel charge. enter the answer to 2 decimal places.(b) determine the cumulative distribution function of nickel charge.