A 0.896 g sample of impure magnesite, MgCO3, was decomposed with HCl; the liberated CO 2 was collected on calcium oxide and found to weigh 0.2881 g. Calculate the percentage of magnesium in the sample.

Consider the smelting of iron ore which consists of Fe2O3 and Fe3O4. If Fe is produced in the pig iron, and FeO is produced in the slag, what are the chemical equations involved?

A 6.35 kg mixed-mineral sample contains chromite (FeCr2O4) as the only chromium-bearing ore. The sample is subjected to an industrial process, using a ferrosilicon alloy as a reducing agent, which quantitatively converts all of the chromium into 12.5 kg of a ferrochrome alloy (stainless steel) which is 15.4% Cr by mass. What is the percentage of chromite (FeCr2O4) in the original sample?

Mass of KxFe(C2O4)y · zH2O : 4.70 g Mass of sample : 0.175 g Mass of FeCl3 used in preparation : 1.60 g Molarity of standard NaOH used : 0.100 V1, volume of standard NaOH required for first equivalence point : 7.750 mL V2, volume of standard NaOH required for second equivalence point : 19.70 mL Calculate the mass of iron in the sample :

How many energy levels are there in the valence band of a single crystal of potassium with a mass of 6.05 mg

Aluminum metal and sulfuric acid produce aluminum sulfate and hydrogen gas. Write the balanced equation and classify the reaction?

A sample of 0.2500 g of an antimony alloy is taken and converted into Sb2O4 by appropriate processes. Since the product brought to constant weight is 0.1305 g, calculate the percentage of antimony in the alloy (Sb = 121g / mol, 0 = 16 g / mol).

Consider the series of reactions to synthesize the alum (KAl(SO4 )2 · xH2O(s)) Assuming an excess of the other reagents, from one mole of aluminum Al (s), how many moles of alum will be produced?