The useful metal manganese can be extracted from the mineral rhodochrosite by a two-step process. In the first step, manganese(II) carbonate and oxygen react to form manganese(IV) oxide and carbon dioxide: 2MnCOA9 + 02(g) 2 MnO2(s) + 2 CO2(g)
In the second step, manganese(IV) oxide and aluminum react to form manganese and aluminum oxidide
3Mn02(6)+4Als)3Mnsl20s)
Suppose the yield of the first step is 66% and the yield of the second step is 97'%. Calculate the mass of manganese(II) carbonate required to make 4.0 kg of manganese.
Be sure your answer has a unit symbol, if needed, and is rounded to the correct number of significant digits.

Astudent is given a sample of a blue copper sulfate hydrate. he weighs the sample in a dry covered porcelain crucible and got a mass of 23.875 g for the crucible, lid, and sample. the mass of the empty crucible and lid was found earlier to be 22.652 g. he then heats the crucible to expel the water of hydration, keeping the crucible at red heat for 10 minutes with the lid slightly ajar. on colling, he finds the mass of crucible, lid, and contents to be 23.403 g. the sample was changed in the process to very light clue anhydrous cuso4. if there are again 100.0 g of hydrate, how many grams of cuso4 are in it? how many moles of cuso4? (hint: molar mass of cuso4 = 159.6 g / mole. what per cent of the hydrate is cuso4? you may convert the mass of cuso4 to moles.)

Suppose that during that icy hot lab 65,000 j of energy were transferred to 450 g of water at 20°c what would have have been the final temperature of the water

Free answer. the treaty of versailles ended world war i, but some of the terms of the treaty contributed to the beginning of world war ii. which was one of the terms of the treaty? the answer would be "germany was forces to pay reparations to the allied countries.". i hope this .