Many important metals occur as sulfide, arsenide, and antimonide minerals, especially in the Sudbury
mineral complex. The first step in processing these ores involves “roasting” the ore in air to produce the metal
or metal oxide, along with nonmetal oxides that can be serious pollutants if not trapped.
Suppose that you roast 2.00 kg of the mineral greigite, Fe3S4. The balanced equation for the reaction is:
) How many liters of air at 25°C are required for roasting? Assume that air contains 23% O2 by mass,
and that the density of air at 25°C is 1.2 g/L. I got 4800L and got that wrong.
A mixture of KCr(SO4)2 and its hydrate KCr(SO4)2•12H2O has a mass of 1.6336 g. After heating to drive
off all the water, the mass is only 1.4659 g. What is the weight percentage of KCr(SO4)2•12H2O in the original
mixture? Report your answer to 4 significant figures.
Molar masses: KCr(SO4)2 283.22 g/mol; KCr(SO4)2•12H2O 499.40 g/mol.
I got 23.73 percent and also got this wrong
CaCl2 reacts with AgNO3 in aqueous solutions to produce a precipitate of AgCl that can be filtered and
weighed. The balanced equation for the reaction is:
CaCl2 (aq) + 2 AgNO3 (aq) → 2 AgCl (s) + Ca(NO3)2 (aq)
Suppose you have a mixture that contains CaCl2, plus other compounds that do not react with AgNO3. If 0.2918
g of the mixture yields 0.4462 g of AgCl, what is the percentage of CaCl2 in the mixture? I got 59.22 and got this wrong
I understand these are a lot of Q's, but I believe that the and wers that I have should be correct, even after scanning my work again. Whether anyone agrees/disagrees, I would really appreciate any help