"CHEMISTRY: ATOMS, MOLECULAR WEIGHT, WEIGHT and ATOM PERCENT. Let C represent the number of carbon atoms in the molecule, H, the number of hydrogen atoms, O, the number of oxygen atoms, N, the number of nitrogen atoms and SI, the number of silicon atoms. Then the molecular weight (MW) is the sum of the weights of each type of atom. The atom percent (C%, H% ...) is the numberof each type of atom (C, H, ...) as a percentage of the total number of atoms. The weight percent (CWT%, HWT%, ...) is the weight of each type of atom (C, H, ...) as a percentage of total weight of atoms or molecular weight (MW). *** Answers to Problems *** (a) Set C=9, H=23, N=1, O=3 and Si=1. The molecular weight MW=221.4. (b) The atom percents are: carbon C%=24.3, hydrogen H%=62.2, oxygen O%=8.1, nitrogen, N%=2.7 and silicon SI%=2.7. (c) The weight percents are: carbon CWT%=48.8, hydrogen HWT%=10.5, oxygen OWT%= 21.7, nitrogen NWT%=6.3 and silicon SIWT%=12.7. (c) PCSCC, Inc., 1993 Type any key to exit. ||The adhesion promoter A1100 (tm, Union Carbide) has the molecular formula: H(23)C(9)O(3)N(1)Si(1). (a) Calculate its molecular weight. (b) Calculate the atoms percents of the elements. (c) Calculate the weight percents of the elements. Type comma key to see answers. Type (F2) to return to application file."
