Chemistry molecular formular?
925881
First find the moles of BaCO3:\n\nn = m/Mr = 78.8/197 = 0.4 mol, where Mr = 197 the relative molar mass of BaCO3.\n\nThen from the balanced chem. equation: BaCO3  --> BaO + CO2\n\n1 mol of BaCO3 gives 1 mol of CO2, so\n0.4 mol of BaCO3 gives 0.4 mol of CO2\n\nAt last find the volume of CO2 at S.T.P.\n\nV = n*Vm = 0.4*22.4 = 8.96 L, where Vm = 22.4 L/mol the molar volume of a gas at S.T.P. (1 atm, 0 oC)
697475
1) determine the mass of carbon, hydrogen and oxygen.\ncarbon: 7.849 g x (12 / 44) = 2.141 g\nhydrogen: 3.213 g x (2 / 18) = 0.357 g\noxygen: 3.215 - 2.141 - .357 = 0.717 g\n\n2) convert to moles.\ncarbon: 2.141 / 12 = 0.178 mol\nhydrogen: 0.357 / 1 = 0.357 mol\noxygen: 0.717 / 16 = 0.0448 mol\n\n3) divide each molar amount by the lowest value to obtain small integers\ncarbon: 0.178 / 0.0448 = 4\nhydrogen: 0.357  / 0.0448 = 8\noxygen: 0.0448 / 0.0448 = 1\n\nThe empirical formula of the substance is (C4H8O)n\nThe atomic masses add up to 72, which is also the molar mass of the compound. Therefore n=1 and we find C4H8O
1134694
Add a second carbon atom.  The molecular formula for methans is CH4.  The molecular formula for ethene is C2H4.
626494
First one...you'd better look at Wikipedia.\n\nAbout the 2nd one...I don't understand what you mean.\nMaybe...\nDo you need to know how to find the mass of a substance, given the number of moles or vice versa?\n\nWell, you can use this formula:\n\nn= m/M\n\nWhere n=number of moles;\n      m=mass of the substance in grams\n      M=molecular weight or molecular mass of the substance.\n\nMolecular Mass:\nYou have to calculate it in this way:\nConsider the atoms that form that molecule.\nSum the atomic weight of these atoms: you'll obtain the Molecular Mass. If the atom appears twice, for example C2, you have to multiply the Carbon Atomic weight x2.\n\nDo you know how to find the atomic weight? look at the Periodic Table. \nGo to the linkage on the web. The Atomic Number is just below each element.\n\nhttp://www.chem.wisc.edu/areas/reich/handouts/periodic-table.GIF
885936
we have PV = m/M * R * T\nT = t(celsius) + 273\nR = 0.082 = const\nM is the molecular mass\nP is the pressure (1atm = 760 mmHg)\n\nso M = (m*R*T)/(P*V) = 3.6 * 0.082 * (23.4+273)/(4042.4/760 * 0.183 )= 90 g/mol\n\nwith the percentages we can find the compound \n\nthe formula is CxHyOz (x,y,z is the number of atoms)\n\nx : y : z = %C/M(C) : %H/M(H) : %O/M(O) = 40/12 : 6.71/1 : 53.28/16 = 3.33 : 6.71 : 3.33 = x : 2x : x\n\nwe can use this table to find the answer\nx=1 ; M = 30 : CH2O\nx=2 ; M = 60 : C2H4O2\nx=3 ; M = 90 : C3H6O3\nso the formula is C3H6O3
75087
without knowing the specifics of your problem, the formula I think you're asking for is deltaH=H(products)-H(reactants). You get the H values for your products and reactants from tables, multiply them by their coefficients, add all the reactants and all the products, the subtract reactants from products.\n\nThe only other enthalpy equation I can think of is \nH=E+PV where E=energy, P=pressure, and V=volume.
29071
Well, look in the periodic table of the elements and find the molecular weight. The molecular weight tells you how many grams are in one mole of that element. Once you know the amount of grams that correspond to 1 mole, you do the math.\nGood luck!
655605
Apply the formula of\n\nM = molar strength wanted ( in M )\nW = molecular weight of the compound in question (in g/mol)\nV = the volume you wish to make (in mL)\nNo. = weight of compund needed (in grams)\n\napply to the formula\n\nNo. = (V * M * W)/1000 \n\nThen dissolve No. into the amoult of V you need (using a gradlated volumetric flask up to the volume you wanted)
295569
The styrene answer above is correct but the formula is not. It is C6H5CH=CH2 which is C8H8.
820243
the chemical formula of a hydrate would be:\n\nthe original anhydrous form x nH2O where n is any whole numbers\n\nfor example: CaCl2 (calcium chloride) may form several different hydrates--\nCaCl2 x H2O\nCaCl2 x 2H2O\nCaCl2 x 6H2O
373250
C3H7NO2 \n\nwww.chemfinder.com is a useful resource.  \n\nI hope this helps :)
1040448
ask your chem prof or tutor ..it's hard to explain over the internet!
518616
Check this out....\n\nhttp://www.sciencestuff.com/prod/Chem-Rgnts/C2043
853922
These are the right ones:\n\n2K(s) + 2H2O(l) ---> 2KOH(aq) + H2(g)\nH2SO4(aq) + 2KOH(aq) ---> K2SO4(aq) + 2H2O(l)\nCa(OH)2(aq) + 2HCl(aq) ---> CaCl2(aq) + 2H2O(l)
851916
C:H = 85.63:14.37 (mass ratio)\n= 85.63/12.01:14.37/1.008 (molar ratio)\n= 7.13:14.26\n= 1:2\nSo the empirical formula is CH2 and its empirical molecular weight ≈ 14.03\n\nP1V1/T1 = P2V2/T2\n0.980 * 1/(273.2 + 51.5) = 1.V2/273.2 (at STP of 1 atm and 0°C)\nSo V2 = 0.980 * 273.2/324.7\n= 0.825 L\nThus 3.09 g occupies 0.824 L\nSo 3.09 * 22.4/0.825 g occupies 22.4 L at STP\nie 1 g mole = 83.9\nThus MW of this gas is 83.9\nSo number of empirical units = 83.9/14.03 ≈ 6\nSo the molecular formula is C6H12
906651
2KOH=>K(2)O+H(2)O\n\nFeO+C=>CO+Fe\n\nCa+2AlCl=>CaCl(2)+2Al\n\nP(2)O(5)+3H(2)O=>2H(3)PO(4)\n\n2KI+Pb(NO3)2=>2KNO(3)+PbI(2)
924472
well, it's hard to draw here. but when i want to find a chem structure, i look at http://www.chemfinder.com you can type naproxen sodium into the search box, and it draws out the structural formula and gives you the properties of the molecule. VERY COOL!