Calculate the mass of hydrogen gas obtained when 10 g of zinc reacts with sulphuric acid. The equation represe
481615
Since you're given the mass of zinc, the first step is to find its moles:\nMoles of Zn = mass/ molar mass = 10/65 = 0.154 moles\n\nThen using the balanced equation, compare the mole ratio of zinc with hydrogen. The mole ratio here is 1:1\n\nTherefore moles of hydrogen will also be 0.154\n\nSince you now know the moles for hydrogen, you can find its volume. They almost always ask to calculate the VOLUME of a gas, not it's mass - though if you're asked about the mass, then find it using the formula above; for calculating volume of hydrogen obtained:\n\nmoles of H2 = volume / molar volume\n0.154 = volume / 24 \n(molar volume of a gas at stp is 22.5dm3 and at rtp is 24dm3 - here I'm assuming rtp conditions)\nvolume = 0.154 x 24 = 3.696 dm3
829148
I'll do one, and hopefully that'll help you figure out the rest.\n\n11. The first step is to create a balanced reaction.  I'm doing this from memory, and I could be wrong, so check it.\n2Zn + 2HCl ----> H2 + 2ZnCl\n\nNow figure out how many moles of zinc are in 3255 grams.  The atomic weight (aka the molar mass) of Zn is available from the periodic table:\n3255/65.409 = 49.764 moles\n\nSince you will have 2 moles of ZnCl for every 2 moles of Zn (a 1:1 ratio), you know that you will also end up with 49.764 moles of ZnCl.\n\nFigure out the molar mass of ZnCl by adding the atomic weight of Cl to that of Zn, then multiply this number by the total number of moles:\n(65.409 + 35.453)(49.764) = 5019.276g ZnCl\n\nUse the same method to solve all the rest.
860818
From the reaction, 2 moles LiOH react with one mole CO2.\n\nSo find out how many moles of LiOH you have in 454 g LiOH.  Then divide by two (according to the first sentence above) and you have the number of moles of CO2.\n\nFinally multiply the number of moles of CO2 by the molecular weight of CO2 and you will get the mass of CO2.\n\nIf you don't understand you should do something else.  Nothing to do with chemistry.
819316
CuSO4+Fe = FeSO4+Cu\nCompute the number of atoms of CuSO4 in 7 gms of it, the number of atoms in 2gm of Fe. Choose the smaller number of the two. That is the number of atoms of Cu formed. Compute its weight.
761151
first you must calculate the number of moles for oxygen, with its molar mass of 32.00g/mol.\n\nonce you have that value, you know from the balanced equation that the number of moles of SO3 will be equivalent to twice the number of moles of oxygen.\nusing this value for moles of SO3, you can then find the mass, knowing that SO3's molar mass is equivalent to 80.07g\nthe mass of SO3 produced will then be 0.9280*mass of SO3. (92.8% yield means only 92.8% of expected was produced)
502184
5H2O2(aq)+2KMnO4(aq)+\n3H2SO4(aq)-->\n2MnSO4(aq)+K2SO4(aq)+\n8H2O(l)+5O2(g)
879225
625g ZnS x 1mol ZnS/97g ZnS x 1mol Zn(NO3)2/1mol ZnS x 189g Zn(NO3)2/1mol Zn(NO3)2 x 100/85 = 1433g Zn(NO3)2\n\nZn=65 S=32 NO3=62
783249
Change it to 1.27 × 10^4\n\nYour value for Specific Heat of Zn is only 3 sigfigs, thus, your answer can only be up to 3 sigfigs.
759497
1) determine the mass of carbon, hydrogen and oxygen.\ncarbon: 7.432 g x (12 / 44) = 2.027 g\nhydrogen: 4.057 g x (2 / 18) = 0.451 g\noxygen: 3.383 - 2.027 - .451 = 0.905 g\n\n2) convert to moles.\ncarbon: 2.027 / 12 = 0.169 mol\nhydrogen: 0.451 / 1 = 0.451 mol\noxygen: 0.905 / 16 = 0.0566 mol\n\n3) divide each molar amount by the lowest value to obtain small integers\ncarbon: 0.169 / 0.0566 = 3\nhydrogen: 0.451  / 0.0566 = 8\noxygen: 0.0566 / 0.0566 = 1\n\nThe empirical formula of the substance is (C3H8O)n\nThe atomic masses add up to 60, which is also the molar mass of the compound. Therefore n=1 and we find C3H8O
748872
Cu2+ (aq)  +  Zn (s) -->  Cu (s) + Zn2+ (aq)
600524
Give the mass of one reagent in a reaction, and ask for the mass of another. A word equation or chemical equation must be provided.\n\neg:\n\nWhat mass of nitrogen gas is required to produce 45.0 g of ammonia, according to the reaction below ?\n\n         N2   + 3 H2   ---> 2 NH3\n\n\nTo solve the problem\n\na) convert mass of NH3 to moles (2.65 mol)\nb) use stoichiometry - find moles of N2 needed (1.32 mol) \nc) convert moles of N2 to mass (37.0 g)
984026
You need to find the heats of formation of each species (will come from a standard table) and use this equation to get the heat of reaction:\n\n(delta)H = sum of heat of formation of products - sum of heat of formation of reactants\n\nEach heat of formation will be multiplied by its stoichiometric ratio, and the physical state will be important (especially that of water, as the heat of formation of steam is higher than that of liquid water).  You will not find a heat of formation for oxygen gas, because by definition there is no heat of formation for an element.
968504
The balanced reaction is:\n3C + 2SO2  ---->  CS2  +  2CO2\n\nNotice that in the balanced reaction that the number of moles of sulfur dioxide that react and the moles of carbon dioxide produced are the same.\n\nSince the molar mass of SO2 is 64g/mol and you are starting with 8.00 grams, this means that you are starting with 1/8 of a mole of sulfur dioxide.  Since carbon dioxide is produced at the same amount, 1/8 of a mole of CO2 will be produced.
746377
The equation is S + O2 ===> SO2. That says that 1 g-atom of S reacts with 1 mol of O2 to give 1 mol SO2. The first step is to find the limiting reagent--the one that runs out first.\n\n20g S x (1 g-atomS/32g S)  = 0.675 g-atomS\n\n160g O2 x (1 molO2/32g O2) = 5 molO2\n\nSo the S runs out first; that is the limiting reagent.\n\nSo 0.675 g-atomS  x (1 mol SO2/1 g-atomS) x (64gSO2/1 molSO2) = 5/8 x 64 = 40g SO2
889364
i am just starting chemistry, but i think that you multiplied hydrogen (H) by four, when it should be multiplied by 3, like the Oxygen (O).  otherwise it is correct.  you sould round to whatever your teacher tells you or to 6 significant digits, because that is the least amount you have.  the correct answer should be \n\n(considering your atomic weights are correct)\n\n[12.0107 x 3] + [1.00794 x 5] + [15.9994 x 3] + [1.00794 x 3] =  \n\ncalculate it out and it should work fine... (i think)
715558
OK, but you need to look up atomic weights or calculate molar mass.\n\n   Grams = Moles x molar mass  OR  moles x atomic mass\n\n    Moles = Grams/(molar mass) OR Grams/(atomic mass)
729915
E = cp*m * ∆T; you have cp (specific heat), m and ∆T.  Find how many moles 1kg of iron is, and subsitute that for the mass in the formula for cp.  You can get that information here http://en.wikipedia.org/wiki/Iron