# Solution a the resultant empirical formula for

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Solution (a) The resultant empirical formula for glucose is CH 2 O. (b) The empirical formula for nitrous oxide is the same as its molecular formula, N 2 O.
CHEM 181 – CHEMISTRY FOR ENGINEERS 1A – ATOMS, MOLECULES AND NOMENCLATURE - UKZN 17 TYPES OF FORMULAS IONS Ionization or a group of atoms that have a net positive or negative charge. Cation formation - e e.g. Na atom Na - + ion (cation) 11 protons 11 protons 11 electrons 11 electrons 1s 2 2s 2 2p 6 3s 1 1s 2 2s 2 2p 6 = [Ne] noble gas configuration Structural formulas show the order in which atoms are bonded. Perspective drawings also show the three-dimensional array of atoms in a compound.
CHEM 181 – CHEMISTRY FOR ENGINEERS 1A – ATOMS, MOLECULES AND NOMENCLATURE - UKZN 18 Anion formation + e e.g. Cl atom Cl - - ion (anion) 17 protons 17 protons 17 electrons 18 electrons 1s 2 2s 2 2p 6 3s 2 3p 5 1s 2 2s 2 2p 6 3s 2 3p 6 = [Ar] noble gas configuration When atoms lose or gain electrons, they become ions. Cations are positive and are formed by elements on the left side of the periodic chart. Anions are negative and are formed by elements on the right side of the periodic chart. Ionic Bonds : Ionic compounds (such as NaCl) are generally formed between metals and nonmetals.
CHEM 181 – CHEMISTRY FOR ENGINEERS 1A – ATOMS, MOLECULES AND NOMENCLATURE - UKZN Writing Formulas Because compounds are electrically neutral, one can determine the formula of a compound this way: The charge on the cation becomes the subscript on the anion. The charge on the anion becomes the subscript on the cation. If these subscripts are not in the lowest whole-number ratio, divide them by the greatest common factor. Practice exercise 1. Give the chemical symbol, including mass number, for each of the following ions: (a) The ion with 22 protons, 26 neutrons, and 19 electrons; (b) The ion of sulfur that has 16 neutrons and 18 electrons. Solution . .
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CHEM 181 – CHEMISTRY FOR ENGINEERS 1A – ATOMS, MOLECULES AND NOMENCLATURE - UKZN 2. How many protons and electrons does the Se 2– ion possess?
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3. Predict the charge expected for the most stable ion of barium and for the most stable ion of oxygen. .