Determine the empirical and molecular formulas of each of the following substances:
(a) Styrene, a compound substance used to make Styrofoam® cups and insulation, contains 92.3% C and 7.7% H by mass and has a molar mass of 104 g/mol.
(b) Caffeine, a stimulant found in coffee, contains 49.5% C, 5.15% H, 28.9% N, and 16.5% O by mass and has a molar mass of 195 g/mol.
(c) Monosodium glutamate (MSG), a flavor enhancer in certain foods, contains 35.51% C, 4.77% H, 37.85% O, 8.29% N, and 13.60% Na, and has a molar mass of 169 g/mol.
![](data:image/png;base64,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)
Empirical formula of this compound is CH.
To determine the molecular formula, we need to find out how many times is molar mass higher than the mass of empirical formula:
![](data:image/png;base64,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)
Molecular formula is C8H8.
b) Empirical formula of caffeine:
![](data:image/png;base64,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)
Empirical formula of caffeine is C4H5N2O. The sum of atomic masses from empirical formula is 97 g/mol.
![](data:image/png;base64,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)
Molecular formula of caffeine is 2 × empirical formula = C8H10N4O2
c) Empirical formula of MSG:
![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAB14AAAAhBAMAAACLsxTKAAAACXBIWXMAAABkAAAAZAAPlsXdAAAAKlBMVEVHcEwAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAHrpZrAAAADnRSTlMAiES7EflVIjNm1XeZquq7HFAAAA8jSURBVHja7FrdbxTXFT873p39tLQ2trFBlZblIxBA2jYPgeZlMQqhDpHWyK4hysMasOUkPKyhLpT2YUixEG0qrRNKZUSlLbESJ33ZhCiFoko2oqAofcBRFClS/5iec7/m3jszawseSqQ5sj0r39+c87vnnjNz7t0DEMv/VXZtb275eQkg8dFtuFYLQ7Twd3x8FH/CRt1T9wCyNw7CwjYvXH1qfLwIML23SSaCkvkzQ+Gngcl4OWKJpaOccGtvX6e8W6wChOVrFvM12Vt+3Ft+GHZ/AgoAszCVrqUr4eoPlfeh6iKsMBNBSTEUamrOx8sRSywd5Uy+UqKrQ3/C8vUcpmG64VxtOPL9mWlowzkP83W+mtpbgYlw9RdgN35YhhUnnEGKoQBejRcjlljWk8PeqW343nPLfSpf3YEhf7zOXpuvsx+S/L2Xi/r7dXSQLlPZChy3b+XqIdnGa3+Px0wEESmOghf3bA4bjiWWWPzt44LnuZiSGTit8nU7fO/vT6ssXzezH5I5+Jl+f/Lfy3Q5mKxljlu3CvWQoPfxsTc9ZiKAoHwlFPQ3LoUNxxJLLL64Y8Ar2VRD5usPsKSGLwLL1xY/dwIqW5f1248l+6u094TLM8etW6X6HKX1yqExZiKISAkS/4RUKWQ4llhiUe+/lczJGpzALSikPJmvE+mWAiz0jGIW4RvYrYh6eGtTV3ADCjg+nW5AsmbdytUfZ2/VbB0eMBM2gvKVoeBFlq+B4VhiiUVKdsn5ZTHTcr3L8AdVD9fy+g61BjOQqNAP37CaCt7GcnfG8Vx4OVsM3ErqJ2ATwIzbhM3MhI2gfCWU66UgVQ0ZjuV5lxcA0uujHKytGs8M2bjFjbH60cngG827573uYv7qAVgY5a/OxZt1HzA7WlrT87V7/G/6/Yn6NKzNjb8J3+0L3MrVU76uwYBbJxNBRLZ/iFDdRffx1yHDsTxnMgxQpaxKUjpUKQKOtJMPxGC65+6wD23wX542fe/CsRKDDGV7+vwcZYcgJfbBh3igQYZl4pW4Uc3ib++XfHNVRg7lqI6ZHYRET9WYQlIoUlPwpcMEJCCcfkmH6PRx0KIvYfe/0ChxLfjXi9AjK9YXILODPrynEc9VLRSWu2nx5FuERFsfek/8f9gLuxXVwwX5gZsIKOeDAOcaYcN8Gg6PEvMrIad3Qy6WyDBXC6XJkgHfVgosNEcM82jQnOrT0N2v67YiIkS3irdGAAizW6/43ErrTioZhjCXvbEOd1OFzdc5dRDMBpvzcO9dWRP1VF3tdIN2NuPjo6xhJl3J3/ic11MlWPWPN6jdBhZPN7O9gz4kV4E3lHfQotVyoyxiJH6tVCEZIof/nS7qrD6C5HfmlHZt54pCeoSiJ6DKwVD6RreQQT+yY2grFNTOMrxpyNATLYn6/g6jX0G++ZS3bgARHEZn4Eu4d5CihC66DGzMxRJpuvoL0iWUMiM6i8BCMwTFA0WD1Yk1YLvf0G1FRIhuISwNLGCiD95RkYArDp0nReseQFjL3urM3VZh8U15U2A22GyHUkGoLxR19aLT5iFrmHEqDvCGm50AH/vaqd0mXXRrc3Deh5Qn4IifIN6U1XKjLH5DX1doGzciBzCUqWkYZ2cjaZVsJ9waUxTsEeowASmh9CeMbiGDflTHUKEN6Zq2KQxpGjL0REt++stOox/ce9pbN4AIDNNa0qqcpyihiy5LG3OxQJquzsEIbb+ZUm7Eqi+MheYIigeMBrsTa8l2v67b7kIJ6lZHAdeDwFVgx+tccMWh86TYYbuNMJc92+rM3VZh8XWrd6CkSgi66zDU5dv5Jv76xZfotPFYw0yy4ub54+gnkB7ztVO7TWYMjt+B1K8UpP0fOOM/WKt3rJYbaZGmkvK0fCVy/NzTZ5UvrLjWS+pMvuIYU1DSYQJSQum/ZXQLGfSjOobI1And6cGmIUPPj+UAe4z6MHA1GyV+0Uvl1sZcLJCmq7ejs1mFiUovMiO+jAQWmtPAeKBosDqxFI0TYbobVr6ORASRXe0yIEVkXv1n2czXkElZycYR5rKfq3TmbuerzTd5AMwGm8QfX5OlzN9l9U8PUb/ThjXMDH45y0GvyEcGgUS7jVv7EAsFBWnPV5sKQhbNlhtpMYegOZavqyLzEArO7YWGxiqfGctSjay77jBX5PcIyS6dThMQmFD6J41uIZN+oGMIJidx+FMMVO70VbCbhjhC6Bk4u8FUWX3qQUn1mQDq+YoepdXEKKELpG9NT+7CMu7eWXYirVzMKJku/s2j6d7JukSart4EXZggUikZUWhY8BdazZW9gZMHKBqYUwWN/I0Vply5P6i7BhG6zSDiaeCrJWCuLfeTpBZXPGDXnBRbdxthhg95KIq7Cp1wvixyrg2C1WBzJXH0Bn+oqXeM6+mdNqxhJlPtu8Ze0SfL24sKJNptupqvwnxJQdpd7aaCkEWz5UZanMf/8up9RuQrQiHBvxKUrPLwClIfohpstgcFWHsOU+RPQXTpdJyAwITSv250Cxn0gx1DTqW7zkxla4q82TTEEEJPopmjMwiU9RJm5qkHpaefBaAodjXpjTZfwiihC7i50kh1PyTaiVt13cVEyXJx/XZyyXkikJareU5JpWREoZuP/IVWcyUExgNFA3OqoLEVhgqCBnd/UHcNInQP8UJehhFLA1/tIxGRvrtwxW271qR484mFMMKHeSiKuwydcL4scgCmqnaDzd1uXiw7NdBOBP1OG17R570nRzgo528FeLsNeiIzgJ6SEC+7pO8Wpqpmy420iFsB+K++f2Xk8i1eLAlWu+HmESz3Hf3R6EpFcgqiS6fjBDgmgr7eLWTRD3QMdTdxj0GmuleMosZvGmIIoWcO9mmHCS9FyE8FYFPoqBj8MOpuUXJlosZfErn6+6jxA5pzqcRgqwkT7JK8hDO4j/MobKmu4+LXWs5Kvi2Qlqt5TkmlQzq6yBaPLbRJA+PhdYwG5lROA/d9qzlBw3e/qbsWodsKImBp4Ktd4ptTv0zmK27atSbF1t1GGOHDPNSJO8/XML4sct6H+d1Wg02m2MV3JHTOk1V6VKcNfyfCZahQaZ94AnP+VoC327j1C2yXISD4+5YPQYsls+VGWkTvOGN6vhIUHJ6vklUbUg8h/ySBj6xD+Fzcypt4mCJ/CqJLp+MEOCaKvtYtZNAP6RhK0eOenL6zqjldbxpiCKHnXxR5SXqkt5/rjaukyNYSVzPDooS2jgv4YvgEt4a5d9ZzcbaYaOcaAmm5+jTtMaVSZkShr/JtHy20/5QkBMZDGaOBO5XRyFdg+RLY7jd0s4gI082DyA8jhldqPyYgnWupk1tacbDsWpPiyWYizOjnHurAnasI48si52Z150WrwaYAIl/hNoidMi+eRKcNfQGPssKTsavN9ssCxNpt8HFQ72osKAj+bvEhaLFhttxIi7kSjHh6PUzQGbyOaazakGjhdHK/xomWy+XdvIkHFelTkF06nSbAMRH09W4hg35Ix1AKPmemksugFTV60xBHcD0L8Ak+bZF5OaIgHa52KHk7DuqAqHI3uWOdelhZEBTRGa6Hq5nBKGGLCo/gQLrVXID9kxd1F8tF01xcqHd5l7ISabp6BF/BM1IpGtHQ7mZPLrRSzGhQPGA0cKcyGotF54mgIdwf0M0iIkw3DyIVRoQHX+33BMSIFOc8qJZWHGy75qR4spkIM/o5nQjufj0cxpdFTuLKD2A12AyCqIfh8Ad7eQHfTXErO234WiQ8oGLX6X+Q+KytQKzdJj0+3uoeXlGQLU0QB08MghbNlhtpMfPtLx5z3Bo9iUabBF2Ds7/TWG37FNJFSD74a9kPscE3mqhIn4Ls0uk0AYaJoq91C1n0gx1D2UU60P/TjlsNRd5qGmIIoefYnm9LENIUIv+ZKcpidM3/9jxikB30NECrSBWATZjdfdQ4+7zc5WkA6kKIMi+2sbSWRVpNipLhFfYVRCs91Cjs6Xu/rbuYUTJdnMONz+xfBNJydbb9Fd7BlZIRDZ35BuRCS8WcBsUDRgN3KqfxYKHKaCj327p5RITpNoMICK+pPUrA5MHyP3x34Yrbdu1J9Q8FEGb4kIciucvQCefLI+d/7ZwxixNBFMffZZdsvFOIKazX42BjERhEELv1tLJawQ+wjXBwFst5IIQT4mFzXdIoh01IYX2VYGdpqbVfxn0zO7szk3nZ9YII8v5ccdx77z+53bwwyftlzgsXsLmCwQcHnrFIGwXMlC8bF/n6y7OuCMebUhzkRq/YS3xuUeI8Kqw1MZHaqGGENKWz4R/wgT4ttBBBDFVjtoKGhswvvcxM9ucik4e5ABxrQGPXGqir6TkRVCjAUvMB/mpJm9QGsNx1YAjFpFArQHM3y2dJOFaATgqnUP5EbZc4QgIsrTNtyStTm5rZNMRaroXPBlmqHkZZoMyty9/Ne2AvpNqgti2am2jdUWddj/44Y3/9Evoe7+x/BHK7YT6dcrrYIKLS+3H9jAwPc8E+Cqs+CSIrV+6OqCDurW4sNR/gr5a0SW0A4q0DQygmhVyBxfrrasd8OuV0sSn15Ti9fkaGh7nE0BP6a607kyu3X8kg9ivO3xUf4K2Wn5s1BjD65cAQkkmhV2CxWM7QCvAtX3VsxNObM7dfySBW56KZX3iqJW3SGITpd3sKm0kmhV6BxWLZ/frIbJivC6D71QlKZNPq17VqSZs0BnuXQyshmCsmhVyBxWJZ/YpTwKphbmv5+nWhg4VRLefvql97Oj4yqiVtUhnc1QlxnYCfRb5Mq4RIx/nINRaL6lc8zKWv3kDua1n9WgXPdTA1quX8XfIBEOl4Yu6HsV8rgxOdUDd8P38jmRSVEOr4mO8Li+XvVzzM5ShcmnMU4+Pksl/poNxNZ3D0DMwpzcTaTWfwov+eMhhDLpkUe4UJ3xYWy6fF8zke5vITPu3lxp+F/gWn52RQogBIKCAfYLwnBbP61dn81pAwQApBMSlWQsD3hcXaKAWFnByeJshqCDIYjt2gDBVGdbBeqwyig+SwWDMwmBSvAYvF8mua3w+ib+98LamCcDYYipZqst2iz0EstjFgsVjWVlYEO3FQCCoII3goWqpfk/ZlvdjKgMViOQ2TByndr3fggWipfrKxX7cyYLFYxoY0WU0PRpfRigrGj+99XLVUT2NqP7wqM7YxYP1r/QYFekYB+nTfHQAAAABJRU5ErkJggg==)
Empirical formula of MSG is C5H8NO4Na. The sum of atomic masses of empirical formula is 169 g/mol, the same as molar mass. Empirical and molecular formula are identical.
Determine the empirical and molecular formulas of each of the following substances:
(a) Styrene, a compound substance used to make Styrofoam® cups and insulation, contains 92.3% C and 7.7% H by mass and has a molar mass of 104 g/mol.
(b) Caffeine, a stimulant found in coffee, contains 49.5% C, 5.15% H, 28.9% N, and 16.5% O by mass and has a molar mass of 195 g/mol.
(c) Monosodium glutamate (MSG), a flavor enhancer in certain foods, contains 35.51% C, 4.77% H, 37.85% O, 8.29% N, and 13.60% Na, and has a molar mass of 169 g/mol.
Empirical formula of this compound is CH.
To determine the molecular formula, we need to find out how many times is molar mass higher than the mass of empirical formula:
Molecular formula is C8H8.
b) Empirical formula of caffeine:
Empirical formula of caffeine is C4H5N2O. The sum of atomic masses from empirical formula is 97 g/mol.
Molecular formula of caffeine is 2 × empirical formula = C8H10N4O2
c) Empirical formula of MSG:
Empirical formula of MSG is C5H8NO4Na. The sum of atomic masses of empirical formula is 169 g/mol, the same as molar mass. Empirical and molecular formula are identical.