Achemist prepares a solution of potassium permanganate (kmno4) by measuring out 3.8 umol of potassium permanganate into a 100 ml volumetric flask and filling the flask to the mark with water. calculate the concentration in mol/l of the chemist's potassium permanganate solution. round your answer to 2 significant digits. x 5 ? explanation check

In a laboratory determination of the atomic weight of tin, a sample of tin is weighed in a crucible. nitric acid is added, and the reaction proceeds to give a hydrated tin(iv)oxide plus no2and h2o. the hydrated tin(iv)oxide is then heated strongly and reacts as follows: sno2.xh2o(s)sno2(s)+ xh2o(g)the sno2is finally cooled and weighed in the crucible. explain the effect on the calculated atomic weight of tin that would result from each of the following experimental errors: (a)considerable spattering occurs when the nitric acid is added to the tin.(b)the hydrated tin(iv)oxide is not heated sufficiently to change it completely to tin oxide.