7 . What is the velocity of a neutron if it has a de Broglie wavelength of 75 fm 75 fm ?

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7 . What is the velocity of a neutron if it has a de Broglie wavelength of 75 fm75 fm ?AVECBONUS QUESTIONThis question is a bit more challenging . It will not be graded8 . In one beaker , 10.0 mI of chromic chloride is mixed with 150 mI , of 0.400 M chromic nitrate . In aseparate beaker , 20.0 mI of 0.500 M sodium carbonate was mixed withth 150 mI of 0.420 M sodiumarbonateFinally , the contents of the two beakers are mixed , and 1 . 3138 of precipitate is formedDetermine the molarity of the chromic chloride solution . In addition , calculculate the molarity of eachon ( including spectator ions ) after the precipitation process is compcomplete