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Calculate the empirical formula of methyl acetate, a solvent commonly used in some paints, inks and adhesive. The chemical analysis shows the percentage composition of the compound: 48.64% C, 8.16% H, and 43.20% O.
A compound was found to contain 49.98% C, and 10.47% H. The molar mass of the compound is 58.12 g/mol. Determine the molecular formula.
what mass carbon 4 oxide is produced when excess dilute hcl is added to the rescue
A steel containing 0.002% N is to be nitrided to yield a nitrogen content of 0.12% at depth of 4 mm from the surface. The nitriding atmosphere is equivalent to a surface concentration of 0.35% N. How long is to be the nitriding process? The steel is BCC at the nitriding temperature of 700°C.
If a sample contains 6.75 mol of Na2SO4, how many moles of sodium atoms, sulfur atoms, and oxygen atoms does it have?
A sample of Xe gas has a volume of 4.34×103 mL at 1.74 atm and 96.71 K. Calculate the new pressure (in atm), when the temperature of the gas is decreased by 22.0 K. Assume the volume does not change.
Arrange the following compounds (H2O, H2S, Br2, NaC1) in increasing Viscosity
#1) Using Quantum Theory to explain give the stable ions that Ge and Bi can form.
#2) The following series of equations represent a method of decomposing water vapour to produce hydrogen and oxygen.
1) 6 FeCl2(s) + 8 H2O(g) + 636 kJ → 2 Fe3O4(s) + 12 HCl(g) + 2 H2(g)
2) Fe3O4(s) + 3/2 Cl2(g) + 6 HCl(g) → 3 FeCl3(s) + 3 H2O(g) + ½ O2(g) + 249 kJ
3) 3/2 FeCl2(s) + 3/4 Cl2(g) → 3/2 FeCl3(s) + 87 kJ a)
Show that the net result of the three reactions is the decomposition of water. b) Use Hess’s law and the enthalpy changes for the reactions to determine the enthalpy change for the decomposition of one mole of water.
Water hardness is caused by the presence of Ca2+ and Mg2+ ions. One way of
removing these ions is to add sodium carbonate, Na2CO3(s), which causes
precipitation of calcium carbonate, CaCO3(s), and magnesium carbonate,
MgCO3(s). A 5.0 L volume of water has a Ca2+ concentration of 0.0040 mol/L.
What is the maximum mass of sodium carbonate that can be added to this
volume without causing any precipitate to form? The Ksp for CaCO3(s) is 4.8x10-9
at 25 oC.
#1) Using Quantum Theory to explain give the stable ions that Ge and Bi can form.
#2) The following series of equations represent a method of decomposing water vapour to produce hydrogen and oxygen.
1) 6 FeCl2(s) + 8 H2O(g) + 636 kJ → 2 Fe3O4(s) + 12 HCl(g) + 2 H2(g)
2) Fe3O4(s) + 3/2 Cl2(g) + 6 HCl(g) → 3 FeCl3(s) + 3 H2O(g) + ½ O2(g) + 249 kJ
3) 3/2 FeCl2(s) + 3/4 Cl2(g) → 3/2 FeCl3(s) - 87 kJ a)
Show that the net result of the three reactions is the decomposition of water. b) Use Hess’s law and the enthalpy changes for the reactions to determine the enthalpy change for the decomposition of one mole of water.
