Engineers in south africa are hired to determine whether a river that passes through a pyrochroite (mn(oh)2) deposit meets the standards for drinking water (drinking water standard for mn = 50 ppb). the river is in contact with solid mn(oh)2 (pksp = 14.3) and has a ph of 8.0. determine the concentration of mn2+ in the river in mg/l. also, determine the ph at which the concentration of mn2+ would meet the drinking water standard. (answers: [mn2+] = 275.2 mg/l; ph=9.87).

3.09 lab: reaction of metals 1 which combinations of substances resulted in a chemical change? for each metal that participated in a chemical change, write the type of metal it is, based on your examination of the periodic table. were there any metallic compounds that did not react with either the acid or the base? write the type of metal, based on your examination of the periodic table. make a general statement about the reactivity of the metals in this experiment.

Why must humans find substitutes for many minerals found on earth? (a) form at an extremely slow rate (b) controlled by other countries (c) too deep in the earth to collect

Convert a speed of 201 cm/s to units of inches per minute. also, show the unit analysis by dragging components into the unit‑factor slots.