CHEM 1201 Chapter : Chapter 2
Document Summary
Chapter 2: atoms, molecules and ions: atomic theory of matter, the theory that atoms are the fundamental building blocks of matter reemerged in the early. 19th century, championed by john dalton: daltons postulate states that all matter is made of tiny particles called atoms. All atoms of a given element have identical chemical properties. Atoms of different elements have distinct properties: in chemical reactions, atoms of an element are not changed into different types of atoms; instead, a chemical reaction changes the way atoms are combined. Atoms are neither created nor destroyed: atoms form chemical compounds by combining in whole-number ratios. 24mg: (23. 985045 mass) (0. 7890 fraction) = 18. 92 amu weighted mass. 25mg: (24. 985839 mass) (0. 1000 fraction) = 2. 499 amu weighted mass. 26mg: (25. 982595 mass) (0. 1110 fraction) = 2. 884 amu weighted mass: periodicity, when you look at the chemical properties of elements, you see a repeating pattern as atoms of the elements get heavier (more protons, neutrons and electrons), groups.
