Author: Anonymous

How many molecules of P4O10 are there in 0.3398 moles of P4O10? 

A chemist makes 0.850 L of silver nitrate, AgNO3, working solution by adding distilled water to 0.250 L of a 0.419 M stock solution of silver nitrate in water. Calculate the concentration of the chemist’s working solution. (If you wish, you can show math work for possible partial credit.)

The chemical formula for diethyl ether is (CH3CH2)2O . Calculate the molar mass of diethyl ether. Round your answer to 2  decimal place. (If you wish, you can show math work for possible partial credit.)

The chemical formula for hydrogen fluoride is HF.A chemist measured the amount of hydrogen fluoride produced during an experiment. She finds that846 g of hydrogen fluoride is produced. Calculate the number of moles of hydrogen fluoride produced.

Measurements show that unknown compound X has the following composition: element  mass % carbon 74.02% hydrogen 8.710% nitrogen 17.27% Write the empirical chemical formula of X?

Balance the following equation (note: if the answer is 1 write 1 in the space, do not leave it blank):  [1] FeCl3 (aq) + [2] H2S (g) 

Write the oxidation number of the selected element in each of the following substances: S in SO42- is [S] F in F2 is [F] Cl in KClO3 is [Cl] Br in PBr5 is [Br]

This is the chemical formula for zinc bromate: Zn(BrO3)2. Calculate the mass percent of bromine in zinc bromate. Round your answer to one decimal place. (If you wish, you can show math work for possible partial credit.)

Determine the percent yield of a reaction that produces 28.65 g of Fe when 0.3131 mol of Fe2O3 react with excess Al according to the following reaction.                        Fe2O3(s) + 2 Al(s)  →  Al2O3(s) + 2 Fe(s)

Balance the following equation (note: if the answer is 1 write 1 in the space, do not leave it blank):  [1] Al(NO3)3 + [2] Na2S