The ionic radii of Ca2 and F- ions are 0.100 nm and 0.133 nm, respectively. Calculate the force of attraction between these two ions at their equilibrium inter ionic separation (i. e., when the ions just touch one another). Express your answer in N in engineering notation to two significant figures. Do not include the units.

For a research project, a student decided to test the effect of the lead(ii) ion (pb2+) on the ability of salmon eggs to hatch. this ion was obtainable from the water‐soluble salt, lead(ii) nitrate, which the student decided to make by the following reaction. pbo(s) + 2 hno3(aq) → pb(no3)2(aq) + h2o losses of product for various reasons were expected, and a yield of 86.0% was expected. in order to have 5.00 g of product at this yield, how many grams of pbo should be reacted? (assume that sufficient nitric acid, hno3, would be used.)