What mass of CoS is produced from 4.84 g Co(NO3)2 and 115 mL of 0.225 M K2S solution? _____ g (Give answer to correct sig figs in units of g)

4.79 Phosphoric add (H3PO4) is important in the production of both fertilizers and detergents. It is distributed commercially as a solution with a concentration of about 14.8 M. Approximately 2.1 X l09 gallons of this concentrated phosphoric acid solution is produced annually in the United States. Assuming that all of this H3PO4 is produced by the reaction below, what mass of the mineral fluoruapatite (Ca5(PO4)3F) would be required each year? Ca5( PO4)3F+5H2SO43H3PO4+5CaSO4+HF

Small quantities of oxygen gas can be generated in the laboratory by the decomposition of hydrogen peroxide. The unbalanced equation for the reaction is H2O2(uz/)-? H2O(/) + O2(g) Calculate the mass of oxygen produced when 10.00 g of hydrogen peroxide decomposes.

Write the balanced chemical equation for the complete combustion of adipic acid, an organic acid containing 49.31% C, 6.90% H, and the remainder O, by mass.

The pictures below show a molecular-scale view of a chemical reaction between H2 and CO to produce methanol, CH3OH The box on the left represents the reactants at the instant of mixing, and the box on the right shows what is left once the reaction has gone to completion. D Was there a limiting reactant in this reaction? If so, what was it? Write a balanced chemical equation for this reaction. As usual, your equation should use the smallest possible whole number coefficients for all substances.

4.59 Aluminum dissolves in HCI according to the equation written below, whereas copper does not react with HCl. 2Al( s )+6HCl( aq ) 2AlCl 3 ( aq )+ 3H 2 ( g ) A 35.0-g sample of a copper—aluminum alloy is dropped into 750 mL of 3.00 M HCl, and the reaction above proceeds as far as possible. If the ahoy contains 77.1% Al by mass, what mass of hydrogen gas would be produced?

4-89 If 7.0 kg of is added to 11.0 kg of to form which reactant is in excess?

A common method for analyzing for the nickel content of a sample is to use a precipitation reaction. Adding the organic compound dimethylgly-oxime to a solution containing Ni2+ ions precipitates a red solid. Derive the empirical formula for the red solid based on the following composition: Ni, 20.315%; C, 33.258%; H, 4.884%; 0, 22.151%; and N, 19.392%.

A 100.0-g mixture made up of NaCl03, Na2CO3, NaCl, and NaHCO3 is heated, producing 5.95 g of oxygen, 1.67 g of water, and 14.5 g of carbon dioxide. NaCl does not react under the conditions of the experiment. The equations for the reactions that take place are: 2NaClO3(s)2NaCl(s)+3O2(g)Na2CO3(s)2Na2O(s)+CO2(g)2NaHCO3(s)Na2O(s)+2CO2(g)+H2O Assuming 100% decomposition of NaClO3, Na2CO3, and NaHCO3, what is the composition of the mixture in grams?