Concepts (chapter 3)
Calculate the average atomic mass of isotopes
(exact weight of isotope #1) (abundance of isotope #1) + (exact weight of isotope #2) (abundance of isotope #2) = average atomic weight of the element
Explain the relationship between Dalton's atomic theory and the Law of Conservation of Mass, Law of Definite Proportions, and Law of Multiple Proportions.
According to Dalton, atoms of the same element will always have the same mass (Law of Conservation of Mass) and for each compound there is a unique composition (Law of Definite Proportions). If two or more different compounds are composed of the same two elements, then the ratio of the masses of the elements is always a ratio of small whole numbers (Law of Multiple Proportions).
Calculate the percent by mass of a compound
Step 1: find the atomic mass of each element in the molecule Step 2: find the mass combination of each element Step 3: find the total molecular mass of the molecule Step 4: find the mass percent composition of each element
Calculate the number of each subatomic particle using the periodic table
Step 1: find the atomic number Step 2: find the atomic mass Step 3: atomic mass - atomic number (protons) = neutrons
Calculate molar mass of an element or compound
Step 1: find the relative atomic mass of the element Step 2: multiply by the molar mass constant Step 3: find the molar mass of a molecule composed of 2 atoms
Explain how the radius of an atom is determined
The distance between two nuclei will give the diameter of an atom, the radius is half the diameter
Explain the experimentation done with the cathode ray tube and the gold foil experiment
They were performed to explain observations and test hypotheses.
State and explain the Law of Conservation of Mass, Law of Definite Proportions, and Law of Multiple Proportions.
a.) Law of Conservation of Mass - no detectable gain or loss in mass occurs in chemical reactions b.) Law of Definite Proportion - the elements in a given compound are always combined in the same proportion by mass c.) Law of Multiple Proportions - Whenever two elements form more than one compound, the different masses of one element that combine with the same mass of the other element are in the ratio of small whole numbers
Know the difference between atomic number, mass number, atomic mass
a.) atomic number - the number of protons in the nucleus of an atom b.) mass number - the total number of protons and neutrons in a nucleus c.) atomic mass - the mass of an atom of a chemical element expressed in atomic mass units (approximately equivalent to the mass number)
Summarize the 5 essential points of Dalton's theory
a.) elements are made of extremely small particles called atoms b.) atoms of a given element are identical in size, mass, and other properties c.) atoms cannot be subdivided, created, or destroyed d.) atoms of different elements combine in simple whole-number ratios to form chemical compounds e.) atoms are combined, separated, or rearranged in chemical reactions
Describe the properties and locations of the subatomic particles
a.) proton - inside the nucleus, positively charge b.) neutron - inside the nucleus, no charge c.) electron - orbits the nucleus, negative charge